20915656 has 32 divisors (see below), whose sum is σ = 42408000. Its totient is φ = 9637056.

The previous prime is 20915651. The next prime is 20915659. The reversal of 20915656 is 65651902.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20915651) 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 7 ways as a sum of consecutive naturals, for example, 3765 + ... + 7483.

It is an arithmetic number, because the mean of its divisors is an integer number (1325250).

Almost surely, 2^20915656 is an apocalyptic number.

It is an amenable number.

20915656 is an abundant number, since it is smaller than the sum of its proper divisors (21492344).

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

20915656 is a wasteful number, since it uses less digits than its factorization.

20915656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3781 (or 3777 counting only the distinct ones).

The product of its (nonzero) digits is 16200, while the sum is 34.

The square root of 20915656 is about 4573.3637511136. The cubic root of 20915656 is about 275.5225590139.

The spelling of 20915656 in words is "twenty million, nine hundred fifteen thousand, six hundred fifty-six".