21934624 has 48 divisors (see below), whose sum is σ = 46543896. Its totient is φ = 10137600.

The previous prime is 21934613. The next prime is 21934667. The reversal of 21934624 is 42643912.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 18766224 + 3168400 = 4332^2 + 1780^2 .

It is a super-2 number, since 2×21934624² = 962255460042752, which contains 22 as substring.

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, 32854 + ... + 33514.

Almost surely, 2^21934624 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21934624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23271948).

21934624 is an abundant number, since it is smaller than the sum of its proper divisors (24609272).

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

21934624 is a wasteful number, since it uses less digits than its factorization.

21934624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 749 (or 741 counting only the distinct ones).

The product of its digits is 10368, while the sum is 31.

The square root of 21934624 is about 4683.4414696887. The cubic root of 21934624 is about 279.9261029479.

It can be divided in two parts, 219 and 34624, that added together give a palindrome (34843).

The spelling of 21934624 in words is "twenty-one million, nine hundred thirty-four thousand, six hundred twenty-four".