21612324 has 24 divisors (see below), whose sum is σ = 51183328. Its totient is φ = 7096320.

The previous prime is 21612319. The next prime is 21612373. The reversal of 21612324 is 42321612.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21612324.

It is an unprimeable number.

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, 12637 + ... + 14244.

Almost surely, 2^21612324 is an apocalyptic number.

It is an amenable number.

21612324 is an abundant number, since it is smaller than the sum of its proper divisors (29571004).

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

21612324 is a wasteful number, since it uses less digits than its factorization.

21612324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26955 (or 26953 counting only the distinct ones).

The product of its digits is 576, while the sum is 21.

The square root of 21612324 is about 4648.9056776837. The cubic root of 21612324 is about 278.5482856326.

Adding to 21612324 its reverse (42321612), we get a palindrome (63933936).

The spelling of 21612324 in words is "twenty-one million, six hundred twelve thousand, three hundred twenty-four".