20556889632 has 288 divisors, whose sum is σ = 62609863680. Its totient is φ = 6386688000.

The previous prime is 20556889567. The next prime is 20556889687. The reversal of 20556889632 is 23698865502.

20556889632 is a `hidden beast` number, since 2 + 0 + 556 + 8 + 89 + 6 + 3 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×20556889632² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32577957 + ... + 32578587.

It is an arithmetic number, because the mean of its divisors is an integer number (217395360).

Almost surely, 2^20556889632 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 20556889632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31304931840).

20556889632 is an abundant number, since it is smaller than the sum of its proper divisors (42052974048).

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

20556889632 is a wasteful number, since it uses less digits than its factorization.

20556889632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808 (or 797 counting only the distinct ones).

The product of its (nonzero) digits is 6220800, while the sum is 54.

The spelling of 20556889632 in words is "twenty billion, five hundred fifty-six million, eight hundred eighty-nine thousand, six hundred thirty-two".