21803229 has 16 divisors (see below), whose sum is σ = 36915840. Its totient is φ = 12458880.

The previous prime is 21803227. The next prime is 21803239. The reversal of 21803229 is 92230812.

It is a happy number.

It is not a de Polignac number, because 21803229 - 2¹ = 21803227 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21803227) 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 15 ways as a sum of consecutive naturals, for example, 57492 + ... + 57869.

It is an arithmetic number, because the mean of its divisors is an integer number (2307240).

Almost surely, 2^21803229 is an apocalyptic number.

It is an amenable number.

21803229 is a deficient number, since it is larger than the sum of its proper divisors (15112611).

21803229 is a wasteful number, since it uses less digits than its factorization.

21803229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115377 (or 115371 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21803229 is about 4669.3927870763. The cubic root of 21803229 is about 279.3660359270.

The spelling of 21803229 in words is "twenty-one million, eight hundred three thousand, two hundred twenty-nine".