23187881 has 4 divisors (see below), whose sum is σ = 24551892. Its totient is φ = 21823872.

The previous prime is 23187859. The next prime is 23187929. The reversal of 23187881 is 18878132.

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 16736281 + 6451600 = 4091^2 + 2540^2 .

It is a cyclic number.

It is not a de Polignac number, because 23187881 - 2⁶ = 23187817 is a prime.

It is a super-2 number, since 2×23187881² = 1075355650540322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23187811) 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, 681980 + ... + 682013.

It is an arithmetic number, because the mean of its divisors is an integer number (6137973).

Almost surely, 2^23187881 is an apocalyptic number.

It is an amenable number.

23187881 is a deficient number, since it is larger than the sum of its proper divisors (1364011).

23187881 is a wasteful number, since it uses less digits than its factorization.

23187881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1364010.

The product of its digits is 21504, while the sum is 38.

The square root of 23187881 is about 4815.3796319709. The cubic root of 23187881 is about 285.1589592359.

The spelling of 23187881 in words is "twenty-three million, one hundred eighty-seven thousand, eight hundred eighty-one".