21804634 has 8 divisors (see below), whose sum is σ = 32730048. Its totient is φ = 10894620.

The previous prime is 21804623. The next prime is 21804637. The reversal of 21804634 is 43640812.

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

It is not an unprimeable number, because it can be changed into a prime (21804637) by changing a digit.

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, 829 + ... + 6655.

It is an arithmetic number, because the mean of its divisors is an integer number (4091256).

Almost surely, 2^21804634 is an apocalyptic number.

21804634 is a deficient number, since it is larger than the sum of its proper divisors (10925414).

21804634 is a wasteful number, since it uses less digits than its factorization.

21804634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7700.

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 21804634 is about 4669.5432324800. The cubic root of 21804634 is about 279.3720365802.

The spelling of 21804634 in words is "twenty-one million, eight hundred four thousand, six hundred thirty-four".