22242221 has 4 divisors (see below), whose sum is σ = 22959744. Its totient is φ = 21524700.

The previous prime is 22242211. The next prime is 22242251. The reversal of 22242221 is 12224222.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22242221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22242221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22242211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 358715 + ... + 358776.

It is an arithmetic number, because the mean of its divisors is an integer number (5739936).

Almost surely, 2^22242221 is an apocalyptic number.

It is an amenable number.

22242221 is a deficient number, since it is larger than the sum of its proper divisors (717523).

22242221 is an equidigital number, since it uses as much as digits as its factorization.

22242221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717522.

The product of its digits is 256, while the sum is 17.

The square root of 22242221 is about 4716.1659215935. The cubic root of 22242221 is about 281.2285345922.

Adding to 22242221 its reverse (12224222), we get a palindrome (34466443).

The spelling of 22242221 in words is "twenty-two million, two hundred forty-two thousand, two hundred twenty-one".