81131135 has 8 divisors (see below), whose sum is σ = 97450800. Its totient is φ = 64842624.

The previous prime is 81131129. The next prime is 81131137. The reversal of 81131135 is 53113118.

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

It is a cyclic number.

It is not a de Polignac number, because 81131135 - 2²⁰ = 80082559 is a prime.

It is a super-2 number, since 2×81131135² = 13164522132776450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81131135.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81131137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1610 + ... + 12839.

It is an arithmetic number, because the mean of its divisors is an integer number (12181350).

Almost surely, 2^81131135 is an apocalyptic number.

81131135 is a deficient number, since it is larger than the sum of its proper divisors (16319665).

81131135 is a wasteful number, since it uses less digits than its factorization.

81131135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15577.

The product of its digits is 360, while the sum is 23.

The square root of 81131135 is about 9007.2823315360. The cubic root of 81131135 is about 432.9082382841.

It can be divided in two parts, 8113113 and 5, that added together give a palindrome (8113118).

The spelling of 81131135 in words is "eighty-one million, one hundred thirty-one thousand, one hundred thirty-five".