131205181 has 2 divisors, whose sum is σ = 131205182. Its totient is φ = 131205180.

The previous prime is 131205149. The next prime is 131205187. The reversal of 131205181 is 181502131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130988025 + 217156 = 11445^2 + 466^2 .

It is a cyclic number.

It is not a de Polignac number, because 131205181 - 2⁵ = 131205149 is a prime.

It is a super-2 number, since 2×131205181² = 34429599042485522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131205187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65602590 + 65602591.

It is an arithmetic number, because the mean of its divisors is an integer number (65602591).

Almost surely, 2^131205181 is an apocalyptic number.

It is an amenable number.

131205181 is a deficient number, since it is larger than the sum of its proper divisors (1).

131205181 is an equidigital number, since it uses as much as digits as its factorization.

131205181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 22.

The square root of 131205181 is about 11454.4830088485. The cubic root of 131205181 is about 508.1403256398.

The spelling of 131205181 in words is "one hundred thirty-one million, two hundred five thousand, one hundred eighty-one".