131641981 has 2 divisors, whose sum is σ = 131641982. Its totient is φ = 131641980.

The previous prime is 131641969. The next prime is 131641987. The reversal of 131641981 is 189146131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99900025 + 31741956 = 9995^2 + 5634^2 .

It is a cyclic number.

It is not a de Polignac number, because 131641981 - 2¹⁷ = 131510909 is a prime.

It is a super-2 number, since 2×131641981² = 34659222323208722, which contains 22 as substring.

It is equal to p_7466038 and since 131641981 and 7466038 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131641987) 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 as a sum of consecutive naturals, namely, 65820990 + 65820991.

It is an arithmetic number, because the mean of its divisors is an integer number (65820991).

Almost surely, 2^131641981 is an apocalyptic number.

131641981 is the 7257-th centered pentagonal number.

It is an amenable number.

131641981 is a deficient number, since it is larger than the sum of its proper divisors (1).

131641981 is an equidigital number, since it uses as much as digits as its factorization.

131641981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 131641981 is about 11473.5339368479. The cubic root of 131641981 is about 508.7035905966.

The spelling of 131641981 in words is "one hundred thirty-one million, six hundred forty-one thousand, nine hundred eighty-one".