21207296 has 72 divisors (see below), whose sum is σ = 49006944. Its totient is φ = 9052160.

The previous prime is 21207271. The next prime is 21207301. The reversal of 21207296 is 69270212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47651 + ... + 48093.

It is an arithmetic number, because the mean of its divisors is an integer number (680652).

Almost surely, 2^21207296 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 21207296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24503472).

21207296 is an abundant number, since it is smaller than the sum of its proper divisors (27799648).

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

21207296 is a wasteful number, since it uses less digits than its factorization.

21207296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 21207296 is about 4605.1380001038. The cubic root of 21207296 is about 276.7972467901.

The spelling of 21207296 in words is "twenty-one million, two hundred seven thousand, two hundred ninety-six".