21613232 has 40 divisors (see below), whose sum is σ = 43872192. Its totient is φ = 10304000.

The previous prime is 21613213. The next prime is 21613237. The reversal of 21613232 is 23231612.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21613237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30482 + ... + 31182.

Almost surely, 2^21613232 is an apocalyptic number.

It is an amenable number.

21613232 is an abundant number, since it is smaller than the sum of its proper divisors (22258960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21613232 is a wasteful number, since it uses less digits than its factorization.

21613232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 797 (or 791 counting only the distinct ones).

The product of its digits is 432, while the sum is 20.

The square root of 21613232 is about 4649.0033340491. The cubic root of 21613232 is about 278.5521864671.

Adding to 21613232 its reverse (23231612), we get a palindrome (44844844).

The spelling of 21613232 in words is "twenty-one million, six hundred thirteen thousand, two hundred thirty-two".