181131129 has 12 divisors (see below), whose sum is σ = 270656100. Its totient is φ = 116589984.

The previous prime is 181131127. The next prime is 181131163. The reversal of 181131129 is 921131181.

It can be written as a sum of positive squares in 2 ways, for example, as 154629225 + 26501904 = 12435^2 + 5148^2 .

It is not a de Polignac number, because 181131129 - 2¹ = 181131127 is a prime.

It is not an unprimeable number, because it can be changed into a prime (181131127) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 346734 + ... + 347255.

It is an arithmetic number, because the mean of its divisors is an integer number (22554675).

Almost surely, 2^181131129 is an apocalyptic number.

It is an amenable number.

181131129 is a deficient number, since it is larger than the sum of its proper divisors (89524971).

181131129 is a wasteful number, since it uses less digits than its factorization.

181131129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 694024 (or 694021 counting only the distinct ones).

The product of its digits is 432, while the sum is 27.

The square root of 181131129 is about 13458.4965356462. The cubic root of 181131129 is about 565.8018520436.

The spelling of 181131129 in words is "one hundred eighty-one million, one hundred thirty-one thousand, one hundred twenty-nine".