20565936828 has 48 divisors (see below), whose sum is σ = 54453557760. Its totient is φ = 6709452912.

The previous prime is 20565936817. The next prime is 20565936863. The reversal of 20565936828 is 82863956502.

20565936828 is a `hidden beast` number, since 20 + 5 + 6 + 593 + 6 + 8 + 28 = 666.

It is a super-2 number, since 2×20565936828² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2020726 + ... + 2030877.

It is an arithmetic number, because the mean of its divisors is an integer number (1134449120).

Almost surely, 2^20565936828 is an apocalyptic number.

It is an amenable number.

20565936828 is an abundant number, since it is smaller than the sum of its proper divisors (33887620932).

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

20565936828 is a wasteful number, since it uses less digits than its factorization.

20565936828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4051663 (or 4051655 counting only the distinct ones).

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

The spelling of 20565936828 in words is "twenty billion, five hundred sixty-five million, nine hundred thirty-six thousand, eight hundred twenty-eight".