21321532 has 6 divisors (see below), whose sum is σ = 37312688. Its totient is φ = 10660764.

The previous prime is 21321527. The next prime is 21321539. The reversal of 21321532 is 23512312.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2665188 + ... + 2665195.

Almost surely, 2^21321532 is an apocalyptic number.

It is an amenable number.

21321532 is a deficient number, since it is larger than the sum of its proper divisors (15991156).

21321532 is a wasteful number, since it uses less digits than its factorization.

21321532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5330387 (or 5330385 counting only the distinct ones).

The product of its digits is 360, while the sum is 19.

The square root of 21321532 is about 4617.5244449813. The cubic root of 21321532 is about 277.2933591351.

Adding to 21321532 its reverse (23512312), we get a palindrome (44833844).

The spelling of 21321532 in words is "twenty-one million, three hundred twenty-one thousand, five hundred thirty-two".