21382938 has 12 divisors (see below), whose sum is σ = 46329738. Its totient is φ = 7127640.

The previous prime is 21382937. The next prime is 21382943. The reversal of 21382938 is 83928312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20223009 + 1159929 = 4497^2 + 1077^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21382937) 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 5 ways as a sum of consecutive naturals, for example, 593953 + ... + 593988.

Almost surely, 2^21382938 is an apocalyptic number.

21382938 is an abundant number, since it is smaller than the sum of its proper divisors (24946800).

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

21382938 is a wasteful number, since it uses less digits than its factorization.

21382938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1187949 (or 1187946 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 21382938 is about 4624.1688982995. The cubic root of 21382938 is about 277.5593055618.

The spelling of 21382938 in words is "twenty-one million, three hundred eighty-two thousand, nine hundred thirty-eight".