815131980 has 288 divisors, whose sum is σ = 2914748928. Its totient is φ = 182476800.

The previous prime is 815131921. The next prime is 815131981. The reversal of 815131980 is 89131518.

815131980 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (815131981) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1232850 + ... + 1233510.

It is an arithmetic number, because the mean of its divisors is an integer number (10120656).

Almost surely, 2^815131980 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 815131980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1457374464).

815131980 is an abundant number, since it is smaller than the sum of its proper divisors (2099616948).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

815131980 is a wasteful number, since it uses less digits than its factorization.

815131980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737 (or 732 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 36.

The square root of 815131980 is about 28550.5162825473. The cubic root of 815131980 is about 934.1342821328.

The spelling of 815131980 in words is "eight hundred fifteen million, one hundred thirty-one thousand, nine hundred eighty".