21246208 has 36 divisors (see below), whose sum is σ = 42770700. Its totient is φ = 10532864.

The previous prime is 21246193. The next prime is 21246221. The reversal of 21246208 is 80264212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2166784 + 19079424 = 1472^2 + 4368^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37866 + ... + 38422.

It is an arithmetic number, because the mean of its divisors is an integer number (1188075).

Almost surely, 2^21246208 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 21246208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21385350).

21246208 is an abundant number, since it is smaller than the sum of its proper divisors (21524492).

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

21246208 is an equidigital number, since it uses as much as digits as its factorization.

21246208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722 (or 708 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 21246208 is about 4609.3609101480. The cubic root of 21246208 is about 276.9664362622.

The spelling of 21246208 in words is "twenty-one million, two hundred forty-six thousand, two hundred eight".