812131 has 4 divisors (see below), whose sum is σ = 819432. Its totient is φ = 804832.

The previous prime is 812129. The next prime is 812137. The reversal of 812131 is 131218.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 131218 = 2 ⋅65609.

It is a cyclic number.

It is not a de Polignac number, because 812131 - 2¹ = 812129 is a prime.

It is a super-2 number, since 2×812131² = 1319113522322, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (812137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3481 + ... + 3706.

It is an arithmetic number, because the mean of its divisors is an integer number (204858).

2⁸¹²¹³¹ is an apocalyptic number.

812131 is a deficient number, since it is larger than the sum of its proper divisors (7301).

812131 is a wasteful number, since it uses less digits than its factorization.

812131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7300.

The product of its digits is 48, while the sum is 16.

The square root of 812131 is about 901.1831112488. The cubic root of 812131 is about 93.2986506623.

Adding to 812131 its reverse (131218), we get a palindrome (943349).

The spelling of 812131 in words is "eight hundred twelve thousand, one hundred thirty-one".