21804322 has 24 divisors (see below), whose sum is σ = 35177436. Its totient is φ = 10128096.

The previous prime is 21804283. The next prime is 21804329. The reversal of 21804322 is 22340812.

It can be written as a sum of positive squares in 2 ways, for example, as 21799561 + 4761 = 4669^2 + 69^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21804293 and 21804302.

It is not an unprimeable number, because it can be changed into a prime (21804329) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 38868 + ... + 39424.

Almost surely, 2^21804322 is an apocalyptic number.

21804322 is a deficient number, since it is larger than the sum of its proper divisors (13373114).

21804322 is a wasteful number, since it uses less digits than its factorization.

21804322 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642 (or 619 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 21804322 is about 4669.5098243820. The cubic root of 21804322 is about 279.3707040731.

The spelling of 21804322 in words is "twenty-one million, eight hundred four thousand, three hundred twenty-two".