21365564501466 has 32 divisors (see below), whose sum is σ = 49977928660800. Its totient is φ = 6747020368560.

The previous prime is 21365564501419. The next prime is 21365564501539. The reversal of 21365564501466 is 66410546556312.

21365564501466 is a `hidden beast` number, since 2 + 1 + 3 + 6 + 5 + 564 + 5 + 0 + 14 + 66 = 666.

It is a super-2 number, since 2×21365564501466² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10412067445 + ... + 10412069496.

It is an arithmetic number, because the mean of its divisors is an integer number (1561810270650).

Almost surely, 2^{21365564501466} is an apocalyptic number.

21365564501466 is an abundant number, since it is smaller than the sum of its proper divisors (28612364159334).

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

21365564501466 is a wasteful number, since it uses less digits than its factorization.

21365564501466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20824136971 (or 20824136965 counting only the distinct ones).

The product of its (nonzero) digits is 15552000, while the sum is 54.

The spelling of 21365564501466 in words is "twenty-one trillion, three hundred sixty-five billion, five hundred sixty-four million, five hundred one thousand, four hundred sixty-six".