22228821 has 6 divisors (see below), whose sum is σ = 32108310. Its totient is φ = 14819208.

The previous prime is 22228813. The next prime is 22228831. The reversal of 22228821 is 12882222.

It can be written as a sum of positive squares in only one way, i.e., 12680721 + 9548100 = 3561^2 + 3090^2 .

It is not a de Polignac number, because 22228821 - 2³ = 22228813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22228831) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1234926 + ... + 1234943.

It is an arithmetic number, because the mean of its divisors is an integer number (5351385).

Almost surely, 2^22228821 is an apocalyptic number.

It is an amenable number.

22228821 is a deficient number, since it is larger than the sum of its proper divisors (9879489).

22228821 is a wasteful number, since it uses less digits than its factorization.

22228821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2469875 (or 2469872 counting only the distinct ones).

The product of its digits is 2048, while the sum is 27.

The square root of 22228821 is about 4714.7450620368. The cubic root of 22228821 is about 281.1720471369.

The spelling of 22228821 in words is "twenty-two million, two hundred twenty-eight thousand, eight hundred twenty-one".