22518444217 has 4 divisors (see below), whose sum is σ = 22661873956. Its totient is φ = 22375014480.

The previous prime is 22518444209. The next prime is 22518444229. The reversal of 22518444217 is 71244481522.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71244481522 = 2 ⋅35622240761.

It can be written as a sum of positive squares in 2 ways, for example, as 11396843536 + 11121600681 = 106756^2 + 105459^2 .

It is a cyclic number.

It is not a de Polignac number, because 22518444217 - 2³ = 22518444209 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 22518444217.

It is not an unprimeable number, because it can be changed into a prime (22518444517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71714634 + ... + 71714947.

It is an arithmetic number, because the mean of its divisors is an integer number (5665468489).

Almost surely, 2^22518444217 is an apocalyptic number.

It is an amenable number.

22518444217 is a deficient number, since it is larger than the sum of its proper divisors (143429739).

22518444217 is a wasteful number, since it uses less digits than its factorization.

22518444217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143429738.

The product of its digits is 143360, while the sum is 40.

The spelling of 22518444217 in words is "twenty-two billion, five hundred eighteen million, four hundred forty-four thousand, two hundred seventeen".