21616923465 has 32 divisors (see below), whose sum is σ = 38706595200. Its totient is φ = 11446073280.

The previous prime is 21616923439. The next prime is 21616923467. The reversal of 21616923465 is 56432961612.

21616923465 is a `hidden beast` number, since 2 + 1 + 6 + 169 + 23 + 465 = 666.

It is not a de Polignac number, because 21616923465 - 2¹³ = 21616915273 is a prime.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21616923465.

It is not an unprimeable number, because it can be changed into a prime (21616923467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 557226 + ... + 594755.

It is an arithmetic number, because the mean of its divisors is an integer number (1209581100).

Almost surely, 2^21616923465 is an apocalyptic number.

It is an amenable number.

21616923465 is a deficient number, since it is larger than the sum of its proper divisors (17089671735).

21616923465 is a wasteful number, since it uses less digits than its factorization.

21616923465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1152134 (or 1152128 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The spelling of 21616923465 in words is "twenty-one billion, six hundred sixteen million, nine hundred twenty-three thousand, four hundred sixty-five".