20500556 has 6 divisors (see below), whose sum is σ = 35875980. Its totient is φ = 10250276.

The previous prime is 20500541. The next prime is 20500577. The reversal of 20500556 is 65500502.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2562566 + ... + 2562573.

It is an arithmetic number, because the mean of its divisors is an integer number (5979330).

Almost surely, 2^20500556 is an apocalyptic number.

It is an amenable number.

20500556 is a deficient number, since it is larger than the sum of its proper divisors (15375424).

20500556 is a wasteful number, since it uses less digits than its factorization.

20500556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5125143 (or 5125141 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 23.

The square root of 20500556 is about 4527.7539685809. The cubic root of 20500556 is about 273.6876580096.

The spelling of 20500556 in words is "twenty million, five hundred thousand, five hundred fifty-six".