21413536 has 12 divisors (see below), whose sum is σ = 42157962. Its totient is φ = 10706752.

The previous prime is 21413533. The next prime is 21413549. The reversal of 21413536 is 63531412.

It can be written as a sum of positive squares in only one way, i.e., 10890000 + 10523536 = 3300^2 + 3244^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21413536.

It is not an unprimeable number, because it can be changed into a prime (21413531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334555 + ... + 334618.

Almost surely, 2^21413536 is an apocalyptic number.

It is an amenable number.

21413536 is a deficient number, since it is larger than the sum of its proper divisors (20744426).

21413536 is an equidigital number, since it uses as much as digits as its factorization.

21413536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 669183 (or 669175 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 21413536 is about 4627.4762019918. The cubic root of 21413536 is about 277.6916339932.

Adding to 21413536 its reverse (63531412), we get a palindrome (84944948).

The spelling of 21413536 in words is "twenty-one million, four hundred thirteen thousand, five hundred thirty-six".