21468645 has 80 divisors (see below), whose sum is σ = 43211520. Its totient is φ = 10108800.

The previous prime is 21468607. The next prime is 21468649. The reversal of 21468645 is 54686412.

21468645 is a `hidden beast` number, since 2 + 1 + 4 + 6 + 8 + 645 = 666.

It is not a de Polignac number, because 21468645 - 2⁶ = 21468581 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21468649) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 271716 + ... + 271794.

It is an arithmetic number, because the mean of its divisors is an integer number (540144).

Almost surely, 2^21468645 is an apocalyptic number.

It is an amenable number.

21468645 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

21468645 is a wasteful number, since it uses less digits than its factorization.

21468645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 159 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 21468645 is about 4633.4269175201. The cubic root of 21468645 is about 277.9296485370.

The spelling of 21468645 in words is "twenty-one million, four hundred sixty-eight thousand, six hundred forty-five".