23118561 has 16 divisors (see below), whose sum is σ = 34344000. Its totient is φ = 15369984.

The previous prime is 23118559. The next prime is 23118569. The reversal of 23118561 is 16581132.

It is not a de Polignac number, because 23118561 - 2¹ = 23118559 is a prime.

It is a super-4 number, since 4×23118561⁴ (a number of 31 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (23118569) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11170 + ... + 13076.

It is an arithmetic number, because the mean of its divisors is an integer number (2146500).

Almost surely, 2^23118561 is an apocalyptic number.

It is an amenable number.

23118561 is a deficient number, since it is larger than the sum of its proper divisors (11225439).

23118561 is a wasteful number, since it uses less digits than its factorization.

23118561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2365 (or 2359 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 23118561 is about 4808.1764734668. The cubic root of 23118561 is about 284.8745153948.

Adding to 23118561 its reverse (16581132), we get a palindrome (39699693).

The spelling of 23118561 in words is "twenty-three million, one hundred eighteen thousand, five hundred sixty-one".