20831577108 has 24 divisors (see below), whose sum is σ = 48851275200. Its totient is φ = 6908964480.

The previous prime is 20831577103. The next prime is 20831577133. The reversal of 20831577108 is 80177513802.

It is a self number, because there is not a number n which added to its sum of digits gives 20831577108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20831577103) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4359333 + ... + 4364108.

It is an arithmetic number, because the mean of its divisors is an integer number (2035469800).

Almost surely, 2^20831577108 is an apocalyptic number.

It is an amenable number.

20831577108 is an abundant number, since it is smaller than the sum of its proper divisors (28019698092).

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

20831577108 is a wasteful number, since it uses less digits than its factorization.

20831577108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8723647 (or 8723645 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 42.

The spelling of 20831577108 in words is "twenty billion, eight hundred thirty-one million, five hundred seventy-seven thousand, one hundred eight".