21326372 has 6 divisors (see below), whose sum is σ = 37321158. Its totient is φ = 10663184.

The previous prime is 21326363. The next prime is 21326387. The reversal of 21326372 is 27362312.

It can be written as a sum of positive squares in only one way, i.e., 18028516 + 3297856 = 4246^2 + 1816^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2665793 + ... + 2665800.

It is an arithmetic number, because the mean of its divisors is an integer number (6220193).

Almost surely, 2^21326372 is an apocalyptic number.

It is an amenable number.

21326372 is a deficient number, since it is larger than the sum of its proper divisors (15994786).

21326372 is a wasteful number, since it uses less digits than its factorization.

21326372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5331597 (or 5331595 counting only the distinct ones).

The product of its digits is 3024, while the sum is 26.

The square root of 21326372 is about 4618.0485055919. The cubic root of 21326372 is about 277.3143394649.

Adding to 21326372 its reverse (27362312), we get a palindrome (48688684).

The spelling of 21326372 in words is "twenty-one million, three hundred twenty-six thousand, three hundred seventy-two".