22115556 has 18 divisors (see below), whose sum is σ = 55903302. Its totient is φ = 7371840.

The previous prime is 22115549. The next prime is 22115557. The reversal of 22115556 is 65551122.

It can be written as a sum of positive squares in only one way, i.e., 21013056 + 1102500 = 4584^2 + 1050^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (22115557) 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, 307125 + ... + 307196.

It is an arithmetic number, because the mean of its divisors is an integer number (3105739).

Almost surely, 2^22115556 is an apocalyptic number.

It is an amenable number.

22115556 is an abundant number, since it is smaller than the sum of its proper divisors (33787746).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22115556 is a wasteful number, since it uses less digits than its factorization.

22115556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 614331 (or 614326 counting only the distinct ones).

The product of its digits is 3000, while the sum is 27.

The square root of 22115556 is about 4702.7179375336. The cubic root of 22115556 is about 280.6936712381.

Adding to 22115556 its reverse (65551122), we get a palindrome (87666678).

The spelling of 22115556 in words is "twenty-two million, one hundred fifteen thousand, five hundred fifty-six".