131865 has 16 divisors (see below), whose sum is σ = 216000. Its totient is φ = 68672.

The previous prime is 131861. The next prime is 131891. The reversal of 131865 is 568131.

It is a cyclic number.

It is not a de Polignac number, because 131865 - 2² = 131861 is a prime.

It is not an unprimeable number, because it can be changed into a prime (131861) 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, 811 + ... + 959.

It is an arithmetic number, because the mean of its divisors is an integer number (13500).

2¹³¹⁸⁶⁵ is an apocalyptic number.

131865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131865 is a deficient number, since it is larger than the sum of its proper divisors (84135).

131865 is a wasteful number, since it uses less digits than its factorization.

131865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216.

The product of its digits is 720, while the sum is 24.

The square root of 131865 is about 363.1322073295. The cubic root of 131865 is about 50.8990699006.

Subtracting from 131865 its sum of digits (24), we obtain a triangular number (131841 = T₅₁₃).

Adding to 131865 its reverse (568131), we get a palindrome (699996).

The spelling of 131865 in words is "one hundred thirty-one thousand, eight hundred sixty-five".