20564475 has 36 divisors (see below), whose sum is σ = 36285624. Its totient is φ = 10241280.

The previous prime is 20564473. The next prime is 20564491. The reversal of 20564475 is 57446502.

It is not a de Polignac number, because 20564475 - 2¹ = 20564473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20564473) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 161862 + ... + 161988.

It is an arithmetic number, because the mean of its divisors is an integer number (1007934).

Almost surely, 2^20564475 is an apocalyptic number.

20564475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20564475 is a deficient number, since it is larger than the sum of its proper divisors (15721149).

20564475 is a wasteful number, since it uses less digits than its factorization.

20564475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 33.

The square root of 20564475 is about 4534.8070521247. The cubic root of 20564475 is about 273.9718078867.

The spelling of 20564475 in words is "twenty million, five hundred sixty-four thousand, four hundred seventy-five".