20564369 has 24 divisors (see below), whose sum is σ = 25411968. Its totient is φ = 16558080.

The previous prime is 20564359. The next prime is 20564387. The reversal of 20564369 is 96346502.

It is not a de Polignac number, because 20564369 - 2⁸ = 20564113 is a prime.

It is a super-2 number, since 2×20564369² = 845786544736322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20564359) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 79889 + ... + 80145.

It is an arithmetic number, because the mean of its divisors is an integer number (1058832).

Almost surely, 2^20564369 is an apocalyptic number.

It is an amenable number.

20564369 is a deficient number, since it is larger than the sum of its proper divisors (4847599).

20564369 is a wasteful number, since it uses less digits than its factorization.

20564369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365 (or 358 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 20564369 is about 4534.7953647326. The cubic root of 20564369 is about 273.9713371548.

The spelling of 20564369 in words is "twenty million, five hundred sixty-four thousand, three hundred sixty-nine".