21222229 has 8 divisors (see below), whose sum is σ = 25090560. Its totient is φ = 17563056.

The previous prime is 21222211. The next prime is 21222251. The reversal of 21222229 is 92222212.

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

It is a de Polignac number, because none of the positive numbers 2^k-21222229 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 (21222269) 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, 52069 + ... + 52474.

It is an arithmetic number, because the mean of its divisors is an integer number (3136320).

Almost surely, 2^21222229 is an apocalyptic number.

21222229 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21222229 is a deficient number, since it is larger than the sum of its proper divisors (3868331).

21222229 is a wasteful number, since it uses less digits than its factorization.

21222229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104579.

The product of its digits is 576, while the sum is 22.

The square root of 21222229 is about 4606.7590559959. The cubic root of 21222229 is about 276.8621999630.

The spelling of 21222229 in words is "twenty-one million, two hundred twenty-two thousand, two hundred twenty-nine".