21038373 has 10 divisors (see below), whose sum is σ = 31427814. Its totient is φ = 14025528.

The previous prime is 21038363. The next prime is 21038389. The reversal of 21038373 is 37383012.

21038373 is a `hidden beast` number, since 210 + 383 + 73 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20493729 + 544644 = 4527^2 + 738^2 .

It is not a de Polignac number, because 21038373 - 2⁵ = 21038341 is a prime.

It is a super-2 number, since 2×21038373² = 885226276974258, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21038323) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 129786 + ... + 129947.

Almost surely, 2^21038373 is an apocalyptic number.

It is an amenable number.

21038373 is a deficient number, since it is larger than the sum of its proper divisors (10389441).

21038373 is an equidigital number, since it uses as much as digits as its factorization.

21038373 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259745 (or 259736 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 21038373 is about 4586.7606216152. The cubic root of 21038373 is about 276.0603601444.

It can be divided in two parts, 210 and 38373, that added together give a palindrome (38583).

The spelling of 21038373 in words is "twenty-one million, thirty-eight thousand, three hundred seventy-three".