21914568 has 72 divisors (see below), whose sum is σ = 64304370. Its totient is φ = 6739200.

The previous prime is 21914567. The next prime is 21914569. The reversal of 21914568 is 86541912.

21914568 is a `hidden beast` number, since 2 + 1 + 91 + 4 + 568 = 666.

It is an interprime number because it is at equal distance from previous prime (21914567) and next prime (21914569).

It can be written as a sum of positive squares in 3 ways, for example, as 6563844 + 15350724 = 2562^2 + 3918^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21914567) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 11268 + ... + 13068.

Almost surely, 2^21914568 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 21914568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32152185).

21914568 is an abundant number, since it is smaller than the sum of its proper divisors (42389802).

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

21914568 is a wasteful number, since it uses less digits than its factorization.

21914568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1839 (or 1819 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 21914568 is about 4681.2998194946. The cubic root of 21914568 is about 279.8407597950.

The spelling of 21914568 in words is "twenty-one million, nine hundred fourteen thousand, five hundred sixty-eight".