21164565366 has 48 divisors (see below), whose sum is σ = 53396332704. Its totient is φ = 5932922112.

The previous prime is 21164565353. The next prime is 21164565379. The reversal of 21164565366 is 66356546112.

21164565366 is a `hidden beast` number, since 2 + 1 + 1 + 64 + 56 + 536 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (21164565353) and next prime (21164565379).

It is a super-4 number, since 4×21164565366⁴ (a number of 42 digits) contains 4444 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1577971 + ... + 1591326.

It is an arithmetic number, because the mean of its divisors is an integer number (1112423598).

Almost surely, 2^21164565366 is an apocalyptic number.

21164565366 is an abundant number, since it is smaller than the sum of its proper divisors (32231767338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21164565366 is a wasteful number, since it uses less digits than its factorization.

21164565366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3169365 (or 3169362 counting only the distinct ones).

The product of its digits is 777600, while the sum is 45.

The spelling of 21164565366 in words is "twenty-one billion, one hundred sixty-four million, five hundred sixty-five thousand, three hundred sixty-six".