20831865120 has 576 divisors, whose sum is σ = 81736252416. Its totient is φ = 4967930880.

The previous prime is 20831865073. The next prime is 20831865151. The reversal of 20831865120 is 2156813802.

It is a happy number.

It is a super-2 number, since 2×20831865120² (a number of 21 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 28654197 + ... + 28654923.

It is an arithmetic number, because the mean of its divisors is an integer number (141903216).

Almost surely, 2^20831865120 is an apocalyptic number.

20831865120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20831865120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40868126208).

20831865120 is an abundant number, since it is smaller than the sum of its proper divisors (60904387296).

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

20831865120 is a wasteful number, since it uses less digits than its factorization.

20831865120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 835 (or 815 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The spelling of 20831865120 in words is "twenty billion, eight hundred thirty-one million, eight hundred sixty-five thousand, one hundred twenty".