20512990878 has 32 divisors (see below), whose sum is σ = 41330165760. Its totient is φ = 6787122240.

The previous prime is 20512990859. The next prime is 20512990903. The reversal of 20512990878 is 87809921502.

It is a super-2 number, since 2×20512990878² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20512990878.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 516018 + ... + 554346.

It is an arithmetic number, because the mean of its divisors is an integer number (1291567680).

Almost surely, 2^20512990878 is an apocalyptic number.

20512990878 is an abundant number, since it is smaller than the sum of its proper divisors (20817174882).

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

20512990878 is a wasteful number, since it uses less digits than its factorization.

20512990878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38992.

The product of its (nonzero) digits is 725760, while the sum is 51.

The spelling of 20512990878 in words is "twenty billion, five hundred twelve million, nine hundred ninety thousand, eight hundred seventy-eight".