21364208 has 40 divisors (see below), whose sum is σ = 44997120. Its totient is φ = 9789120.

The previous prime is 21364199. The next prime is 21364229. The reversal of 21364208 is 80246312.

It is a congruent number.

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, 8291 + ... + 10557.

It is an arithmetic number, because the mean of its divisors is an integer number (1124928).

Almost surely, 2^21364208 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 21364208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22498560).

21364208 is an abundant number, since it is smaller than the sum of its proper divisors (23632912).

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

21364208 is a wasteful number, since it uses less digits than its factorization.

21364208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2325 (or 2319 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 21364208 is about 4622.1432258207. The cubic root of 21364208 is about 277.4782408608.

The spelling of 21364208 in words is "twenty-one million, three hundred sixty-four thousand, two hundred eight".