21606364215 has 12 divisors (see below), whose sum is σ = 37451031384. Its totient is φ = 11523394224.

The previous prime is 21606364187. The next prime is 21606364259. The reversal of 21606364215 is 51246360612.

21606364215 is a `hidden beast` number, since 2 + 1 + 6 + 0 + 6 + 3 + 642 + 1 + 5 = 666.

It is not a de Polignac number, because 21606364215 - 2⁸ = 21606363959 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21606364215.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 240070669 + ... + 240070758.

It is an arithmetic number, because the mean of its divisors is an integer number (3120919282).

Almost surely, 2^21606364215 is an apocalyptic number.

21606364215 is a deficient number, since it is larger than the sum of its proper divisors (15844667169).

21606364215 is a wasteful number, since it uses less digits than its factorization.

21606364215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480141438 (or 480141435 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 21606364215 in words is "twenty-one billion, six hundred six million, three hundred sixty-four thousand, two hundred fifteen".