23109891 has 8 divisors (see below), whose sum is σ = 35215104. Its totient is φ = 13205640.

The previous prime is 23109883. The next prime is 23109893. The reversal of 23109891 is 19890132.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 23109891 - 2³ = 23109883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (23109893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 550215 + ... + 550256.

It is an arithmetic number, because the mean of its divisors is an integer number (4401888).

Almost surely, 2^23109891 is an apocalyptic number.

23109891 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

23109891 is a deficient number, since it is larger than the sum of its proper divisors (12105213).

23109891 is a wasteful number, since it uses less digits than its factorization.

23109891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100481.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 23109891 is about 4807.2747997176. The cubic root of 23109891 is about 284.8388994112.

The spelling of 23109891 in words is "twenty-three million, one hundred nine thousand, eight hundred ninety-one".