system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it that certain numbers are significant across different religions/cultures?

Is there any reason that certain numbers are repeated across different religions/mythologies and within popular culture? Do different numbers resonate with us in different ways? Do we subconsciously assign significance to ordinary numbers?

Examples:

Jews wandering 40 years in the desert, the flood lasting 40 days, Jesus fasting 40 days, Buddha meditating 40 days.

10 commandments, 10 plagues

On the seventh day, 7 deadly sins (to finally cite culture, 7 dragon balls and 7 chaos emeralds)
gpt
I think many of these are attention bias. You could find examples of many of the lower many cultures:

* 2: Yin & Yang, Adam & Eve/Cain & Abel/Jacob & Esau
* 3: Holy Trinity, three wishes, "I divorce thee" three times, 3 goddesses of the Zorya
* 4: Four elements, four humors, 4 creatures in the chimera, four winds, four leaf clover
* 5: Pentgram as an occult symbol, 5 books of the Torah, 5 Pillars of Islam
* 6: 6-6-6 mark of the beast, 6 symbolic foods in a Seder plate, Six articles of Islamic belief 
* 7: 7 days of creation, 7 levels of hell (in Islam), 7 Dragon balls
* 8: Noble Eightfold Path in Buddhism, circumcision on the 8th day after a child is born, 8 gates to heaven in Islam, the Eight Immortals in China
* 9: 9 is a complete, perfect and divine number in Hinduism, Odin hung on the ash tree for 9 days, Ramadan is on the 9th month of the Islamic calendar
* 10: Ten Commandments, 10 was the holiest number for pythagoreans
* 11: Tiamat creates eleven monsters to take revenge for the death of her husband, The eleventh hour
* 12: Twelve disciples, 12 tribes of Israel, 12 Petals in Anahata (Heart Chakra), Odin had 12 sons, 12 signs of the zodiac
* 13: at age 13 a Jewish boy becomes a man, 13 is considered unlucky or sinister, 13 represents the 1 prophet and 12 Imams in Islam, Jesus had 13 total disciples (Matthias replaced Judas)
* 14: Rama's exile in the forests was 14 years, Osiris torn into fourteen parts
* 15: Julius Caesar killed on March 15th, Passover is the 15th day of Nisan, Quinceañera

The lower number will have more significance in more cultures due to their simplicity and are more common. Numbers divisible by 10 will also have more significance attached due to our base-10 numbering system.