135891 has 16 divisors (see below), whose sum is σ = 230400. Its totient is φ = 77544.

The previous prime is 135887. The next prime is 135893. The reversal of 135891 is 198531.

It is not a de Polignac number, because 135891 - 2² = 135887 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

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 (135893) 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, 171 + ... + 548.

It is an arithmetic number, because the mean of its divisors is an integer number (14400).

2¹³⁵⁸⁹¹ is an apocalyptic number.

135891 is a deficient number, since it is larger than the sum of its proper divisors (94509).

135891 is an equidigital number, since it uses as much as digits as its factorization.

135891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 735 (or 729 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 135891 is about 368.6339647943. The cubic root of 135891 is about 51.4118894307.

The spelling of 135891 in words is "one hundred thirty-five thousand, eight hundred ninety-one".