21122976 has 144 divisors (see below), whose sum is σ = 68693184. Its totient is φ = 5548032.

The previous prime is 21122971. The next prime is 21123013. The reversal of 21122976 is 67922112.

Its product of digits (3024) is a multiple of the sum of its prime divisors (72).

It is not an unprimeable number, because it can be changed into a prime (21122971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 491211 + ... + 491253.

It is an arithmetic number, because the mean of its divisors is an integer number (477036).

Almost surely, 2^21122976 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 21122976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34346592).

21122976 is an abundant number, since it is smaller than the sum of its proper divisors (47570208).

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

21122976 is a wasteful number, since it uses less digits than its factorization.

21122976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 72 counting only the distinct ones).

The product of its digits is 3024, while the sum is 30.

The square root of 21122976 is about 4595.9738902653. The cubic root of 21122976 is about 276.4299118101.

The spelling of 21122976 in words is "twenty-one million, one hundred twenty-two thousand, nine hundred seventy-six".