21397052 has 12 divisors (see below), whose sum is σ = 37816296. Its totient is φ = 10592400.

The previous prime is 21397043. The next prime is 21397069. The reversal of 21397052 is 25079312.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

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, 26078 + ... + 26885.

It is an arithmetic number, because the mean of its divisors is an integer number (3151358).

Almost surely, 2^21397052 is an apocalyptic number.

It is an amenable number.

21397052 is a deficient number, since it is larger than the sum of its proper divisors (16419244).

21397052 is a wasteful number, since it uses less digits than its factorization.

21397052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53068 (or 53066 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 21397052 is about 4625.6947586282. The cubic root of 21397052 is about 277.6203606335.

The spelling of 21397052 in words is "twenty-one million, three hundred ninety-seven thousand, fifty-two".