20557668 has 24 divisors (see below), whose sum is σ = 48115872. Its totient is φ = 6831424.

The previous prime is 20557651. The next prime is 20557673. The reversal of 20557668 is 86675502.

It is a happy number.

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, 1696 + ... + 6632.

It is an arithmetic number, because the mean of its divisors is an integer number (2004828).

Almost surely, 2^20557668 is an apocalyptic number.

It is an amenable number.

20557668 is an abundant number, since it is smaller than the sum of its proper divisors (27558204).

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

20557668 is a wasteful number, since it uses less digits than its factorization.

20557668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5291 (or 5289 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 39.

The square root of 20557668 is about 4534.0564619334. The cubic root of 20557668 is about 273.9415756228.

The spelling of 20557668 in words is "twenty million, five hundred fifty-seven thousand, six hundred sixty-eight".