21372368 has 20 divisors (see below), whose sum is σ = 41778948. Its totient is φ = 10590720.

The previous prime is 21372367. The next prime is 21372413. The reversal of 21372368 is 86327312.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1373584 + 19998784 = 1172^2 + 4472^2 .

It is a super-2 number, since 2×21372368² = 913556227854848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21372367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4103 + ... + 7718.

Almost surely, 2^21372368 is an apocalyptic number.

It is an amenable number.

21372368 is a deficient number, since it is larger than the sum of its proper divisors (20406580).

21372368 is a wasteful number, since it uses less digits than its factorization.

21372368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11942 (or 11936 counting only the distinct ones).

The product of its digits is 12096, while the sum is 32.

The square root of 21372368 is about 4623.0258489435. The cubic root of 21372368 is about 277.5135637122.

The spelling of 21372368 in words is "twenty-one million, three hundred seventy-two thousand, three hundred sixty-eight".