20957764608 has 352 divisors, whose sum is σ = 68339013120. Its totient is φ = 6291947520.

The previous prime is 20957764603. The next prime is 20957764621. The reversal of 20957764608 is 80646775902.

20957764608 is a `hidden beast` number, since 2 + 0 + 9 + 577 + 6 + 4 + 60 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (352).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20957764601) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 41665285 + ... + 41665787.

Almost surely, 2^20957764608 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 20957764608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34169506560).

20957764608 is an abundant number, since it is smaller than the sum of its proper divisors (47381248512).

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

20957764608 is a wasteful number, since it uses less digits than its factorization.

20957764608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 656 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 54.

The spelling of 20957764608 in words is "twenty billion, nine hundred fifty-seven million, seven hundred sixty-four thousand, six hundred eight".