20557688 has 16 divisors (see below), whose sum is σ = 38636880. Its totient is φ = 10254528.

The previous prime is 20557673. The next prime is 20557697. The reversal of 20557688 is 88675502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 845 + ... + 6467.

It is an arithmetic number, because the mean of its divisors is an integer number (2414805).

Almost surely, 2^20557688 is an apocalyptic number.

It is an amenable number.

20557688 is a deficient number, since it is larger than the sum of its proper divisors (18079192).

20557688 is a wasteful number, since it uses less digits than its factorization.

20557688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6086 (or 6082 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 41.

The square root of 20557688 is about 4534.0586674634. The cubic root of 20557688 is about 273.9416644596.

The spelling of 20557688 in words is "twenty million, five hundred fifty-seven thousand, six hundred eighty-eight".