21325564 has 24 divisors (see below), whose sum is σ = 40797008. Its totient is φ = 9694080.

The previous prime is 21325553. The next prime is 21325567. The reversal of 21325564 is 46552312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21325567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 424 + ... + 6544.

Almost surely, 2^21325564 is an apocalyptic number.

It is an amenable number.

21325564 is a deficient number, since it is larger than the sum of its proper divisors (19471444).

21325564 is a wasteful number, since it uses less digits than its factorization.

21325564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6205 (or 6203 counting only the distinct ones).

The product of its digits is 7200, while the sum is 28.

The square root of 21325564 is about 4617.9610219230. The cubic root of 21325564 is about 277.3108371843.

Adding to 21325564 its reverse (46552312), we get a palindrome (67877876).

The spelling of 21325564 in words is "twenty-one million, three hundred twenty-five thousand, five hundred sixty-four".