20887756464 has 40 divisors (see below), whose sum is σ = 53965225072. Its totient is φ = 6961916160.

The previous prime is 20887756433. The next prime is 20887756471. The reversal of 20887756464 is 46465778802.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 919062 + ... + 941514.

Almost surely, 2^20887756464 is an apocalyptic number.

20887756464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20887756464 is an abundant number, since it is smaller than the sum of its proper divisors (33077468608).

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

20887756464 is a wasteful number, since it uses less digits than its factorization.

20887756464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41845 (or 41839 counting only the distinct ones).

The product of its (nonzero) digits is 18063360, while the sum is 57.

The spelling of 20887756464 in words is "twenty billion, eight hundred eighty-seven million, seven hundred fifty-six thousand, four hundred sixty-four".