21258464 has 24 divisors (see below), whose sum is σ = 42230160. Its totient is φ = 10533376.

The previous prime is 21258443. The next prime is 21258481. The reversal of 21258464 is 46485212.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a self number, because there is not a number n which added to its sum of digits gives 21258464.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 677 + ... + 6555.

It is an arithmetic number, because the mean of its divisors is an integer number (1759590).

Almost surely, 2^21258464 is an apocalyptic number.

It is an amenable number.

21258464 is a deficient number, since it is larger than the sum of its proper divisors (20971696).

21258464 is a wasteful number, since it uses less digits than its factorization.

21258464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6002 (or 5994 counting only the distinct ones).

The product of its digits is 15360, while the sum is 32.

The square root of 21258464 is about 4610.6901869460. The cubic root of 21258464 is about 277.0196825974.

The spelling of 21258464 in words is "twenty-one million, two hundred fifty-eight thousand, four hundred sixty-four".