21107372 has 24 divisors (see below), whose sum is σ = 43396752. Its totient is φ = 8856000.

The previous prime is 21107369. The next prime is 21107381. The reversal of 21107372 is 27370112.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17879 + ... + 19022.

It is an arithmetic number, because the mean of its divisors is an integer number (1808198).

Almost surely, 2^21107372 is an apocalyptic number.

21107372 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21107372 is an abundant number, since it is smaller than the sum of its proper divisors (22289380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21107372 is a wasteful number, since it uses less digits than its factorization.

21107372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36929 (or 36927 counting only the distinct ones).

The product of its (nonzero) digits is 588, while the sum is 23.

The square root of 21107372 is about 4594.2760038988. The cubic root of 21107372 is about 276.3618267871.

Adding to 21107372 its reverse (27370112), we get a palindrome (48477484).

The spelling of 21107372 in words is "twenty-one million, one hundred seven thousand, three hundred seventy-two".