21892224 has 64 divisors (see below), whose sum is σ = 59437440. Its totient is φ = 7136256.

The previous prime is 21892207. The next prime is 21892249. The reversal of 21892224 is 42229812.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 21892191 and 21892200.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17442 + ... + 18654.

It is an arithmetic number, because the mean of its divisors is an integer number (928710).

Almost surely, 2^21892224 is an apocalyptic number.

21892224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21892224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29718720).

21892224 is an abundant number, since it is smaller than the sum of its proper divisors (37545216).

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

21892224 is a wasteful number, since it uses less digits than its factorization.

21892224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277 (or 1265 counting only the distinct ones).

The product of its digits is 4608, while the sum is 30.

The square root of 21892224 is about 4678.9126942058. The cubic root of 21892224 is about 279.7456193046.

The spelling of 21892224 in words is "twenty-one million, eight hundred ninety-two thousand, two hundred twenty-four".