21058372 has 6 divisors (see below), whose sum is σ = 36852158. Its totient is φ = 10529184.

The previous prime is 21058369. The next prime is 21058417. The reversal of 21058372 is 27385012.

It can be written as a sum of positive squares in only one way, i.e., 16112196 + 4946176 = 4014^2 + 2224^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21058372.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2632293 + ... + 2632300.

Almost surely, 2^21058372 is an apocalyptic number.

It is an amenable number.

21058372 is a deficient number, since it is larger than the sum of its proper divisors (15793786).

21058372 is a wasteful number, since it uses less digits than its factorization.

21058372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5264597 (or 5264595 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 21058372 is about 4588.9401826566. The cubic root of 21058372 is about 276.1478064293.

Subtracting from 21058372 its product of nonzero digits (3360), we obtain a palindrome (21055012).

The spelling of 21058372 in words is "twenty-one million, fifty-eight thousand, three hundred seventy-two".