21227968 has 56 divisors (see below), whose sum is σ = 45262800. Its totient is φ = 9842688.

The previous prime is 21227933. The next prime is 21227977. The reversal of 21227968 is 86972212.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118503 + ... + 118681.

Almost surely, 2^21227968 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 21227968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22631400).

21227968 is an abundant number, since it is smaller than the sum of its proper divisors (24034832).

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

21227968 is a wasteful number, since it uses less digits than its factorization.

21227968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317 (or 307 counting only the distinct ones).

The product of its digits is 24192, while the sum is 37.

The square root of 21227968 is about 4607.3819029900. The cubic root of 21227968 is about 276.8871544413.

The spelling of 21227968 in words is "twenty-one million, two hundred twenty-seven thousand, nine hundred sixty-eight".