21726804 has 48 divisors (see below), whose sum is σ = 58222080. Its totient is φ = 6236640.

The previous prime is 21726791. The next prime is 21726847. The reversal of 21726804 is 40862712.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1824 + ... + 6839.

It is an arithmetic number, because the mean of its divisors is an integer number (1212960).

Almost surely, 2^21726804 is an apocalyptic number.

It is an amenable number.

21726804 is an abundant number, since it is smaller than the sum of its proper divisors (36495276).

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

21726804 is a wasteful number, since it uses less digits than its factorization.

21726804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8700 (or 8698 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 21726804 is about 4661.2019909032. The cubic root of 21726804 is about 279.0392411500.

The spelling of 21726804 in words is "twenty-one million, seven hundred twenty-six thousand, eight hundred four".