23091881 has 4 divisors (see below), whose sum is σ = 23112132. Its totient is φ = 23071632.

The previous prime is 23091877. The next prime is 23091883. The reversal of 23091881 is 18819032.

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 434281 + 22657600 = 659^2 + 4760^2 .

It is a cyclic number.

It is not a de Polignac number, because 23091881 - 2² = 23091877 is a prime.

It is a super-2 number, since 2×23091881² = 1066469936236322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23091883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8306 + ... + 10731.

It is an arithmetic number, because the mean of its divisors is an integer number (5778033).

Almost surely, 2^23091881 is an apocalyptic number.

It is an amenable number.

23091881 is a deficient number, since it is larger than the sum of its proper divisors (20251).

23091881 is a wasteful number, since it uses less digits than its factorization.

23091881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20250.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 23091881 is about 4805.4012319472. The cubic root of 23091881 is about 284.7648866320.

The spelling of 23091881 in words is "twenty-three million, ninety-one thousand, eight hundred eighty-one".