21224199 has 16 divisors (see below), whose sum is σ = 29351808. Its totient is φ = 13630752.

The previous prime is 21224191. The next prime is 21224207. The reversal of 21224199 is 99142212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21224191) and next prime (21224207).

It is not a de Polignac number, because 21224199 - 2³ = 21224191 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21224191) 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, 10984 + ... + 12770.

It is an arithmetic number, because the mean of its divisors is an integer number (1834488).

Almost surely, 2^21224199 is an apocalyptic number.

21224199 is a deficient number, since it is larger than the sum of its proper divisors (8127609).

21224199 is a wasteful number, since it uses less digits than its factorization.

21224199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1934.

The product of its digits is 2592, while the sum is 30.

The square root of 21224199 is about 4606.9728672958. The cubic root of 21224199 is about 276.8707664785.

The spelling of 21224199 in words is "twenty-one million, two hundred twenty-four thousand, one hundred ninety-nine".