21370944 has 56 divisors (see below), whose sum is σ = 64625728. Its totient is φ = 6105600.

The previous prime is 21370927. The next prime is 21370981. The reversal of 21370944 is 44907312.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is a super-2 number, since 2×21370944² = 913434494902272, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6607 + ... + 9294.

Almost surely, 2^21370944 is an apocalyptic number.

21370944 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21370944 is an abundant number, since it is smaller than the sum of its proper divisors (43254784).

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

21370944 is a wasteful number, since it uses less digits than its factorization.

21370944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15923 (or 15913 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 21370944 is about 4622.8718346932. The cubic root of 21370944 is about 277.5074001760.

The spelling of 21370944 in words is "twenty-one million, three hundred seventy thousand, nine hundred forty-four".