20496961664 has 64 divisors (see below), whose sum is σ = 43022988000. Its totient is φ = 9700042752.

The previous prime is 20496961657. The next prime is 20496961687. The reversal of 20496961664 is 46616969402.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3116972 + ... + 3123540.

Almost surely, 2^20496961664 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 20496961664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21511494000).

20496961664 is an abundant number, since it is smaller than the sum of its proper divisors (22526026336).

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

20496961664 is a wasteful number, since it uses less digits than its factorization.

20496961664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7885 (or 7873 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 53.

The spelling of 20496961664 in words is "twenty billion, four hundred ninety-six million, nine hundred sixty-one thousand, six hundred sixty-four".