21413564 has 12 divisors (see below), whose sum is σ = 37519944. Its totient is φ = 10693584.

The previous prime is 21413549. The next prime is 21413569. The reversal of 21413564 is 46531412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 962 + ... + 6614.

It is an arithmetic number, because the mean of its divisors is an integer number (3126662).

Almost surely, 2^21413564 is an apocalyptic number.

It is an amenable number.

21413564 is a deficient number, since it is larger than the sum of its proper divisors (16106380).

21413564 is a wasteful number, since it uses less digits than its factorization.

21413564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6604 (or 6602 counting only the distinct ones).

The product of its digits is 2880, while the sum is 26.

The square root of 21413564 is about 4627.4792273980. The cubic root of 21413564 is about 277.6917550282.

Adding to 21413564 its reverse (46531412), we get a palindrome (67944976).

The spelling of 21413564 in words is "twenty-one million, four hundred thirteen thousand, five hundred sixty-four".