22891221 has 16 divisors (see below), whose sum is σ = 34017600. Its totient is φ = 15213744.

The previous prime is 22891217. The next prime is 22891223. The reversal of 22891221 is 12219822.

It is not a de Polignac number, because 22891221 - 2² = 22891217 is a prime.

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 (22891223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9115 + ... + 11351.

It is an arithmetic number, because the mean of its divisors is an integer number (2126100).

Almost surely, 2^22891221 is an apocalyptic number.

It is an amenable number.

22891221 is a deficient number, since it is larger than the sum of its proper divisors (11126379).

22891221 is a wasteful number, since it uses less digits than its factorization.

22891221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2625 (or 2619 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 22891221 is about 4784.4770874151. The cubic root of 22891221 is about 283.9376516244.

The spelling of 22891221 in words is "twenty-two million, eight hundred ninety-one thousand, two hundred twenty-one".