21824804 has 12 divisors (see below), whose sum is σ = 40440204. Its totient is φ = 10270464.

The previous prime is 21824801. The next prime is 21824809. The reversal of 21824804 is 40842812.

It can be written as a sum of positive squares in 2 ways, for example, as 15054400 + 6770404 = 3880^2 + 2602^2 .

It is not an unprimeable number, because it can be changed into a prime (21824801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160409 + ... + 160544.

It is an arithmetic number, because the mean of its divisors is an integer number (3370017).

Almost surely, 2^21824804 is an apocalyptic number.

It is an amenable number.

21824804 is a deficient number, since it is larger than the sum of its proper divisors (18615400).

21824804 is a wasteful number, since it uses less digits than its factorization.

21824804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320974 (or 320972 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 29.

The square root of 21824804 is about 4671.7024734030. The cubic root of 21824804 is about 279.4581527909.

The spelling of 21824804 in words is "twenty-one million, eight hundred twenty-four thousand, eight hundred four".