20564362165 has 8 divisors (see below), whose sum is σ = 24681203640. Its totient is φ = 16448843712.

The previous prime is 20564362141. The next prime is 20564362177. The reversal of 20564362165 is 56126346502.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2584502244 + 17979859921 = 50838^2 + 134089^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20564362165 - 2²⁵ = 20530807733 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 (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 296230 + ... + 358999.

It is an arithmetic number, because the mean of its divisors is an integer number (3085150455).

Almost surely, 2^20564362165 is an apocalyptic number.

It is an amenable number.

20564362165 is a deficient number, since it is larger than the sum of its proper divisors (4116841475).

20564362165 is an equidigital number, since it uses as much as digits as its factorization.

20564362165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661511.

The product of its (nonzero) digits is 259200, while the sum is 40.

The spelling of 20564362165 in words is "twenty billion, five hundred sixty-four million, three hundred sixty-two thousand, one hundred sixty-five".