131815 has 8 divisors (see below), whose sum is σ = 162288. Its totient is φ = 102720.

The previous prime is 131797. The next prime is 131837. The reversal of 131815 is 518131.

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

It is not a de Polignac number, because 131815 - 2⁵ = 131783 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131792 and 131801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117 + ... + 526.

It is an arithmetic number, because the mean of its divisors is an integer number (20286).

2¹³¹⁸¹⁵ is an apocalyptic number.

131815 is a deficient number, since it is larger than the sum of its proper divisors (30473).

131815 is an equidigital number, since it uses as much as digits as its factorization.

131815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689.

The product of its digits is 120, while the sum is 19.

The square root of 131815 is about 363.0633553528. The cubic root of 131815 is about 50.8926358577.

Adding to 131815 its reverse (518131), we get a palindrome (649946).

It can be divided in two parts, 131 and 815, that added together give a triangular number (946 = T₄₃).

The spelling of 131815 in words is "one hundred thirty-one thousand, eight hundred fifteen".