21724802 has 8 divisors (see below), whose sum is σ = 35549712. Its totient is φ = 9874900.

The previous prime is 21724783. The next prime is 21724819. The reversal of 21724802 is 20842712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 493724 + ... + 493767.

It is an arithmetic number, because the mean of its divisors is an integer number (4443714).

Almost surely, 2^21724802 is an apocalyptic number.

21724802 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21724802 is a deficient number, since it is larger than the sum of its proper divisors (13824910).

21724802 is a wasteful number, since it uses less digits than its factorization.

21724802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 987504.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 21724802 is about 4660.9872344816. The cubic root of 21724802 is about 279.0306702665.

The spelling of 21724802 in words is "twenty-one million, seven hundred twenty-four thousand, eight hundred two".