21126944 has 12 divisors (see below), whose sum is σ = 41593734. Its totient is φ = 10563456.

The previous prime is 21126943. The next prime is 21126961. The reversal of 21126944 is 44962112.

It can be written as a sum of positive squares in only one way, i.e., 20976400 + 150544 = 4580^2 + 388^2 .

It is not an unprimeable number, because it can be changed into a prime (21126943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330077 + ... + 330140.

Almost surely, 2^21126944 is an apocalyptic number.

It is an amenable number.

21126944 is a deficient number, since it is larger than the sum of its proper divisors (20466790).

21126944 is an equidigital number, since it uses as much as digits as its factorization.

21126944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660227 (or 660219 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 21126944 is about 4596.4055521679. The cubic root of 21126944 is about 276.4472200595.

The spelling of 21126944 in words is "twenty-one million, one hundred twenty-six thousand, nine hundred forty-four".