21804199 has 8 divisors (see below), whose sum is σ = 22140000. Its totient is φ = 21470592.

The previous prime is 21804197. The next prime is 21804227. The reversal of 21804199 is 99140812.

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

It is a cyclic number.

It is not a de Polignac number, because 21804199 - 2¹ = 21804197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21804197) 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 7 ways as a sum of consecutive naturals, for example, 36102 + ... + 36700.

It is an arithmetic number, because the mean of its divisors is an integer number (2767500).

Almost surely, 2^21804199 is an apocalyptic number.

21804199 is a deficient number, since it is larger than the sum of its proper divisors (335801).

21804199 is an equidigital number, since it uses as much as digits as its factorization.

21804199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1097.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 21804199 is about 4669.4966538161. The cubic root of 21804199 is about 279.3701787543.

The spelling of 21804199 in words is "twenty-one million, eight hundred four thousand, one hundred ninety-nine".