21704960 has 72 divisors (see below), whose sum is σ = 53765376. Its totient is φ = 8386560.

The previous prime is 21704957. The next prime is 21704999. The reversal of 21704960 is 6940712.

It is a super-2 number, since 2×21704960² = 942210577203200, which contains 22 as substring.

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, 39407 + ... + 39953.

Almost surely, 2^21704960 is an apocalyptic number.

21704960 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21704960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26882688).

21704960 is an abundant number, since it is smaller than the sum of its proper divisors (32060416).

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

21704960 is an equidigital number, since it uses as much as digits as its factorization.

21704960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 599 (or 585 counting only the distinct ones).

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

The square root of 21704960 is about 4658.8582292231. The cubic root of 21704960 is about 278.9456949929.

The spelling of 21704960 in words is "twenty-one million, seven hundred four thousand, nine hundred sixty".