21458368 has 28 divisors (see below), whose sum is σ = 42793920. Its totient is φ = 10675712.

The previous prime is 21458363. The next prime is 21458377. The reversal of 21458368 is 86385412.

It is a happy number.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21458363) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14193 + ... + 15631.

Almost surely, 2^21458368 is an apocalyptic number.

It is an amenable number.

21458368 is a deficient number, since it is larger than the sum of its proper divisors (21335552).

21458368 is a wasteful number, since it uses less digits than its factorization.

21458368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1684 (or 1674 counting only the distinct ones).

The product of its digits is 46080, while the sum is 37.

The square root of 21458368 is about 4632.3177783913. The cubic root of 21458368 is about 277.8852933253.

The spelling of 21458368 in words is "twenty-one million, four hundred fifty-eight thousand, three hundred sixty-eight".