20664153621 has 32 divisors (see below), whose sum is σ = 31439923200. Its totient is φ = 13407522480.

The previous prime is 20664153613. The next prime is 20664153673. The reversal of 20664153621 is 12635146602.

20664153621 is a `hidden beast` number, since 2 + 0 + 6 + 641 + 5 + 3 + 6 + 2 + 1 = 666.

It is not a de Polignac number, because 20664153621 - 2³ = 20664153613 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20664153821) 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, 181666 + ... + 272636.

It is an arithmetic number, because the mean of its divisors is an integer number (982497600).

Almost surely, 2^20664153621 is an apocalyptic number.

It is an amenable number.

20664153621 is a deficient number, since it is larger than the sum of its proper divisors (10775769579).

20664153621 is a wasteful number, since it uses less digits than its factorization.

20664153621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91206 (or 91200 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 20664153621 in words is "twenty billion, six hundred sixty-four million, one hundred fifty-three thousand, six hundred twenty-one".