21023938 has 12 divisors (see below), whose sum is σ = 34148898. Its totient is φ = 9703200.

The previous prime is 21023923. The next prime is 21023941. The reversal of 21023938 is 83932012.

It can be written as a sum of positive squares in 3 ways, for example, as 5555449 + 15468489 = 2357^2 + 3933^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 30763 + ... + 31438.

Almost surely, 2^21023938 is an apocalyptic number.

21023938 is a deficient number, since it is larger than the sum of its proper divisors (13124960).

21023938 is a wasteful number, since it uses less digits than its factorization.

21023938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62229 (or 62216 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 21023938 is about 4585.1868009930. The cubic root of 21023938 is about 275.9972081913.

The spelling of 21023938 in words is "twenty-one million, twenty-three thousand, nine hundred thirty-eight".