21922812 has 60 divisors (see below), whose sum is σ = 58178736. Its totient is φ = 7197120.

The previous prime is 21922799. The next prime is 21922837. The reversal of 21922812 is 21822912.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 22528 + ... + 23480.

Almost surely, 2^21922812 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 21922812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29089368).

21922812 is an abundant number, since it is smaller than the sum of its proper divisors (36255924).

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

21922812 is a wasteful number, since it uses less digits than its factorization.

21922812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1040 (or 1029 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 21922812 is about 4682.1802613740. The cubic root of 21922812 is about 279.8758463182.

The spelling of 21922812 in words is "twenty-one million, nine hundred twenty-two thousand, eight hundred twelve".