22558981 has 4 divisors (see below), whose sum is σ = 22758732. Its totient is φ = 22359232.

The previous prime is 22558951. The next prime is 22559029. The reversal of 22558981 is 18985522.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1020100 + 21538881 = 1010^2 + 4641^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22558981 is a prime.

It is a super-2 number, since 2×22558981² = 1017815247516722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22558931) 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, 99706 + ... + 99931.

It is an arithmetic number, because the mean of its divisors is an integer number (5689683).

Almost surely, 2^22558981 is an apocalyptic number.

It is an amenable number.

22558981 is a deficient number, since it is larger than the sum of its proper divisors (199751).

22558981 is a wasteful number, since it uses less digits than its factorization.

22558981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199750.

The product of its digits is 57600, while the sum is 40.

The square root of 22558981 is about 4749.6295645029. The cubic root of 22558981 is about 282.5572745230.

It can be divided in two parts, 2255 and 8981, that added together give a square (11236 = 106²).

The spelling of 22558981 in words is "twenty-two million, five hundred fifty-eight thousand, nine hundred eighty-one".