20564973 has 72 divisors (see below), whose sum is σ = 38045280. Its totient is φ = 10523520.

The previous prime is 20564969. The next prime is 20564987. The reversal of 20564973 is 37946502.

20564973 is a `hidden beast` number, since 2 + 0 + 5 + 649 + 7 + 3 = 666.

It is not a de Polignac number, because 20564973 - 2² = 20564969 is a prime.

It is a super-2 number, since 2×20564973² = 845836228981458, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20564923) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 709123 + ... + 709151.

Almost surely, 2^20564973 is an apocalyptic number.

It is an amenable number.

20564973 is a deficient number, since it is larger than the sum of its proper divisors (17480307).

20564973 is a wasteful number, since it uses less digits than its factorization.

20564973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 75 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 36.

The square root of 20564973 is about 4534.8619604129. The cubic root of 20564973 is about 273.9740194167.

The spelling of 20564973 in words is "twenty million, five hundred sixty-four thousand, nine hundred seventy-three".