21764575728 has 240 divisors, whose sum is σ = 72220076032. Its totient is φ = 5987520000.

The previous prime is 21764575727. The next prime is 21764575733. The reversal of 21764575728 is 82757546712.

21764575728 is a `hidden beast` number, since 2 + 1 + 7 + 64 + 5 + 7 + 572 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21764575727) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 6591678 + ... + 6594978.

Almost surely, 2^21764575728 is an apocalyptic number.

21764575728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21764575728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36110038016).

21764575728 is an abundant number, since it is smaller than the sum of its proper divisors (50455500304).

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

21764575728 is a wasteful number, since it uses less digits than its factorization.

21764575728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3564 (or 3555 counting only the distinct ones).

The product of its digits is 6585600, while the sum is 54.

The spelling of 21764575728 in words is "twenty-one billion, seven hundred sixty-four million, five hundred seventy-five thousand, seven hundred twenty-eight".