21124324 has 18 divisors (see below), whose sum is σ = 40031250. Its totient is φ = 9749376.

The previous prime is 21124321. The next prime is 21124339. The reversal of 21124324 is 42342112.

It can be written as a sum of positive squares in 3 ways, for example, as 129600 + 20994724 = 360^2 + 4582^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21124321) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14949 + ... + 16300.

Almost surely, 2^21124324 is an apocalyptic number.

It is an amenable number.

21124324 is a deficient number, since it is larger than the sum of its proper divisors (18906926).

21124324 is a wasteful number, since it uses less digits than its factorization.

21124324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31279 (or 31264 counting only the distinct ones).

The product of its digits is 384, while the sum is 19.

The square root of 21124324 is about 4596.1205380190. The cubic root of 21124324 is about 276.4357919726.

Adding to 21124324 its reverse (42342112), we get a palindrome (63466436).

The spelling of 21124324 in words is "twenty-one million, one hundred twenty-four thousand, three hundred twenty-four".