21970304 has 32 divisors (see below), whose sum is σ = 44961600. Its totient is φ = 10685952.

The previous prime is 21970303. The next prime is 21970339. The reversal of 21970304 is 40307912.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21970303) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2417 + ... + 7055.

It is an arithmetic number, because the mean of its divisors is an integer number (1405050).

Almost surely, 2^21970304 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 21970304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22480800).

21970304 is an abundant number, since it is smaller than the sum of its proper divisors (22991296).

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

21970304 is an equidigital number, since it uses as much as digits as its factorization.

21970304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4690 (or 4678 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 21970304 is about 4687.2490866179. The cubic root of 21970304 is about 280.0778015091.

The spelling of 21970304 in words is "twenty-one million, nine hundred seventy thousand, three hundred four".