21493224 has 48 divisors (see below), whose sum is σ = 60746400. Its totient is φ = 6852384.

The previous prime is 21493217. The next prime is 21493229. The reversal of 21493224 is 42239412.

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

It is not an unprimeable number, because it can be changed into a prime (21493229) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4834 + ... + 8145.

It is an arithmetic number, because the mean of its divisors is an integer number (1265550).

Almost surely, 2^21493224 is an apocalyptic number.

21493224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21493224 is an abundant number, since it is smaller than the sum of its proper divisors (39253176).

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

21493224 is a wasteful number, since it uses less digits than its factorization.

21493224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13014 (or 13007 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 21493224 is about 4636.0785152972. The cubic root of 21493224 is about 278.0356733546.

The spelling of 21493224 in words is "twenty-one million, four hundred ninety-three thousand, two hundred twenty-four".