22221813 has 4 divisors (see below), whose sum is σ = 29629088. Its totient is φ = 14814540.

The previous prime is 22221799. The next prime is 22221817. The reversal of 22221813 is 31812222.

It is a happy number.

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 not a de Polignac number, because 22221813 - 2⁵ = 22221781 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 22221813.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22221817) 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, 3703633 + ... + 3703638.

It is an arithmetic number, because the mean of its divisors is an integer number (7407272).

Almost surely, 2^22221813 is an apocalyptic number.

It is an amenable number.

22221813 is a deficient number, since it is larger than the sum of its proper divisors (7407275).

22221813 is an equidigital number, since it uses as much as digits as its factorization.

22221813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7407274.

The product of its digits is 384, while the sum is 21.

The square root of 22221813 is about 4714.0018031392. The cubic root of 22221813 is about 281.1424959997.

The spelling of 22221813 in words is "twenty-two million, two hundred twenty-one thousand, eight hundred thirteen".