20638207536 has 80 divisors (see below), whose sum is σ = 56666801664. Its totient is φ = 6450045952.

The previous prime is 20638207529. The next prime is 20638207543. The reversal of 20638207536 is 63570283602.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20638207529) and next prime (20638207543).

It is a super-2 number, since 2×20638207536² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 166525 + ... + 262691.

Almost surely, 2^20638207536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20638207536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28333400832).

20638207536 is an abundant number, since it is smaller than the sum of its proper divisors (36028594128).

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

20638207536 is a wasteful number, since it uses less digits than its factorization.

20638207536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96458 (or 96452 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 42.

The spelling of 20638207536 in words is "twenty billion, six hundred thirty-eight million, two hundred seven thousand, five hundred thirty-six".