20508860138 has 12 divisors (see below), whose sum is σ = 33311728998. Its totient is φ = 9465627600.

The previous prime is 20508860101. The next prime is 20508860173. The reversal of 20508860138 is 83106880502.

It can be written as a sum of positive squares in 3 ways, for example, as 10530248689 + 9978611449 = 102617^2 + 99893^2 .

It is a super-2 number, since 2×20508860138² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20508860095 and 20508860104.

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 5 ways as a sum of consecutive naturals, for example, 30338213 + ... + 30338888.

Almost surely, 2^20508860138 is an apocalyptic number.

20508860138 is a deficient number, since it is larger than the sum of its proper divisors (12802868860).

20508860138 is a wasteful number, since it uses less digits than its factorization.

20508860138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60677129 (or 60677116 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 41.

The spelling of 20508860138 in words is "twenty billion, five hundred eight million, eight hundred sixty thousand, one hundred thirty-eight".