20564975 has 6 divisors (see below), whose sum is σ = 25500600. Its totient is φ = 16451960.

The previous prime is 20564969. The next prime is 20564987. The reversal of 20564975 is 57946502.

It is a happy number.

It is not a de Polignac number, because 20564975 - 2²⁴ = 3787759 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 411275 + ... + 411324.

It is an arithmetic number, because the mean of its divisors is an integer number (4250100).

Almost surely, 2^20564975 is an apocalyptic number.

20564975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20564975 is a deficient number, since it is larger than the sum of its proper divisors (4935625).

20564975 is an equidigital number, since it uses as much as digits as its factorization.

20564975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822609 (or 822604 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 20564975 is about 4534.8621809268. The cubic root of 20564975 is about 273.9740282982.

It can be divided in two parts, 2056497 and 5, that added together give a palindrome (2056502).

The spelling of 20564975 in words is "twenty million, five hundred sixty-four thousand, nine hundred seventy-five".