20564564511 has 16 divisors (see below), whose sum is σ = 27537874560. Its totient is φ = 13650567840.

The previous prime is 20564564509. The next prime is 20564564513. The reversal of 20564564511 is 11546546502.

It is an interprime number because it is at equal distance from previous prime (20564564509) and next prime (20564564513).

It is not a de Polignac number, because 20564564511 - 2¹ = 20564564509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20564564511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20564564513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1019320 + ... + 1039298.

It is an arithmetic number, because the mean of its divisors is an integer number (1721117160).

Almost surely, 2^20564564511 is an apocalyptic number.

20564564511 is a deficient number, since it is larger than the sum of its proper divisors (6973310049).

20564564511 is a wasteful number, since it uses less digits than its factorization.

20564564511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21446.

The product of its (nonzero) digits is 144000, while the sum is 39.

The spelling of 20564564511 in words is "twenty billion, five hundred sixty-four million, five hundred sixty-four thousand, five hundred eleven".