181131949 has 8 divisors (see below), whose sum is σ = 183823640. Its totient is φ = 178459200.

The previous prime is 181131919. The next prime is 181131967. The reversal of 181131949 is 949131181.

It can be written as a sum of positive squares in 4 ways, for example, as 9259849 + 171872100 = 3043^2 + 13110^2 .

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 181131949 - 2²⁵ = 147577517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181131919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15139 + ... + 24319.

It is an arithmetic number, because the mean of its divisors is an integer number (22977955).

Almost surely, 2^181131949 is an apocalyptic number.

It is an amenable number.

181131949 is a deficient number, since it is larger than the sum of its proper divisors (2691691).

181131949 is a wasteful number, since it uses less digits than its factorization.

181131949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9471.

The product of its digits is 7776, while the sum is 37.

The square root of 181131949 is about 13458.5269996386. The cubic root of 181131949 is about 565.8027058575.

It can be divided in two parts, 181 and 131949, that multiplied together give a square (23882769 = 4887²).

The spelling of 181131949 in words is "one hundred eighty-one million, one hundred thirty-one thousand, nine hundred forty-nine".