20664128156 has 12 divisors (see below), whose sum is σ = 41328256368. Its totient is φ = 8856054912.

The previous prime is 20664128137. The next prime is 20664128159. The reversal of 20664128156 is 65182146602.

20664128156 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20664128159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 369002261 + ... + 369002316.

It is an arithmetic number, because the mean of its divisors is an integer number (3444021364).

Almost surely, 2^20664128156 is an apocalyptic number.

It is an amenable number.

20664128156 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20664128156 is a wasteful number, since it uses less digits than its factorization.

20664128156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 738004588 (or 738004586 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The spelling of 20664128156 in words is "twenty billion, six hundred sixty-four million, one hundred twenty-eight thousand, one hundred fifty-six".