20638607124681 has 216 divisors, whose sum is σ = 38788619800320. Its totient is φ = 10528052371200.

The previous prime is 20638607124679. The next prime is 20638607124797. The reversal of 20638607124681 is 18642170683602.

It is a happy number.

20638607124681 is a `hidden beast` number, since 2 + 0 + 6 + 3 + 8 + 607 + 1 + 24 + 6 + 8 + 1 = 666.

It is not a de Polignac number, because 20638607124681 - 2¹ = 20638607124679 is a prime.

It is a super-2 number, since 2×20638607124681² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20638607124631) by changing a digit.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 6332802030 + ... + 6332805288.

It is an arithmetic number, because the mean of its divisors is an integer number (179576943520).

Almost surely, 2^{20638607124681} is an apocalyptic number.

20638607124681 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20638607124681 is a deficient number, since it is larger than the sum of its proper divisors (18150012675639).

20638607124681 is a wasteful number, since it uses less digits than its factorization.

20638607124681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6077 (or 6054 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 54.

The spelling of 20638607124681 in words is "twenty trillion, six hundred thirty-eight billion, six hundred seven million, one hundred twenty-four thousand, six hundred eighty-one".