21564205191360 has 168 divisors, whose sum is σ = 79877410201680. Its totient is φ = 5308112037888.

The previous prime is 21564205191323. The next prime is 21564205191371. The reversal of 21564205191360 is 6319150246512.

It is a happy number.

21564205191360 is a `hidden beast` number, since 2 + 1 + 5 + 6 + 420 + 5 + 191 + 36 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 287946070 + ... + 288020949.

It is an arithmetic number, because the mean of its divisors is an integer number (475460775010).

Almost surely, 2^{21564205191360} is an apocalyptic number.

21564205191360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21564205191360 is an abundant number, since it is smaller than the sum of its proper divisors (58313205010320).

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

21564205191360 is a wasteful number, since it uses less digits than its factorization.

21564205191360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 575967055 (or 575967042 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 21564205191360 in words is "twenty-one trillion, five hundred sixty-four billion, two hundred five million, one hundred ninety-one thousand, three hundred sixty".