21269968 has 80 divisors (see below), whose sum is σ = 46743040. Its totient is φ = 9331200.

The previous prime is 21269959. The next prime is 21269971. The reversal of 21269968 is 86996212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 348658 + ... + 348718.

It is an arithmetic number, because the mean of its divisors is an integer number (584288).

Almost surely, 2^21269968 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 21269968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23371520).

21269968 is an abundant number, since it is smaller than the sum of its proper divisors (25473072).

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

21269968 is a wasteful number, since it uses less digits than its factorization.

21269968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 150 counting only the distinct ones).

The product of its digits is 93312, while the sum is 43.

The square root of 21269968 is about 4611.9375537837. The cubic root of 21269968 is about 277.0696432429.

The spelling of 21269968 in words is "twenty-one million, two hundred sixty-nine thousand, nine hundred sixty-eight".