22115881 has 4 divisors (see below), whose sum is σ = 22138564. Its totient is φ = 22093200.

The previous prime is 22115839. The next prime is 22115887. The reversal of 22115881 is 18851122.

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 9865881 + 12250000 = 3141^2 + 3500^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22115881 is a prime.

It is a super-2 number, since 2×22115881² = 978224384812322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22115887) 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, 9810 + ... + 11851.

It is an arithmetic number, because the mean of its divisors is an integer number (5534641).

Almost surely, 2^22115881 is an apocalyptic number.

It is an amenable number.

22115881 is a deficient number, since it is larger than the sum of its proper divisors (22683).

22115881 is a wasteful number, since it uses less digits than its factorization.

22115881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22682.

The product of its digits is 1280, while the sum is 28.

The square root of 22115881 is about 4702.7524918924. The cubic root of 22115881 is about 280.6950462129.

The spelling of 22115881 in words is "twenty-two million, one hundred fifteen thousand, eight hundred eighty-one".