123891 has 8 divisors (see below), whose sum is σ = 168144. Its totient is φ = 81120.

The previous prime is 123887. The next prime is 123911. The reversal of 123891 is 198321.

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

It is not a de Polignac number, because 123891 - 2² = 123887 is a prime.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (123821) 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, 156 + ... + 521.

It is an arithmetic number, because the mean of its divisors is an integer number (21018).

2¹²³⁸⁹¹ is an apocalyptic number.

123891 is a deficient number, since it is larger than the sum of its proper divisors (44253).

123891 is an equidigital number, since it uses as much as digits as its factorization.

123891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741.

The product of its digits is 432, while the sum is 24.

The square root of 123891 is about 351.9815336065. The cubic root of 123891 is about 49.8516938741.

The spelling of 123891 in words is "one hundred twenty-three thousand, eight hundred ninety-one".