21323524 has 24 divisors (see below), whose sum is σ = 38521728. Its totient is φ = 10322400.

The previous prime is 21323521. The next prime is 21323527. The reversal of 21323524 is 42532312.

It is an interprime number because it is at equal distance from previous prime (21323521) and next prime (21323527).

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21323495 and 21323504.

It is not an unprimeable number, because it can be changed into a prime (21323521) 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, 18427 + ... + 19549.

It is an arithmetic number, because the mean of its divisors is an integer number (1605072).

Almost surely, 2^21323524 is an apocalyptic number.

It is an amenable number.

21323524 is a deficient number, since it is larger than the sum of its proper divisors (17198204).

21323524 is a wasteful number, since it uses less digits than its factorization.

21323524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1275 (or 1273 counting only the distinct ones).

The product of its digits is 1440, while the sum is 22.

The square root of 21323524 is about 4617.7401399386. The cubic root of 21323524 is about 277.3019943991.

Adding to 21323524 its reverse (42532312), we get a palindrome (63855836).

The spelling of 21323524 in words is "twenty-one million, three hundred twenty-three thousand, five hundred twenty-four".