131561791 has 2 divisors, whose sum is σ = 131561792. Its totient is φ = 131561790.

The previous prime is 131561753. The next prime is 131561809. The reversal of 131561791 is 197165131.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 131561791 - 2¹⁵ = 131529023 is a prime.

It is a super-2 number, since 2×131561791² = 34617009702255362, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131561711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65780895 + 65780896.

It is an arithmetic number, because the mean of its divisors is an integer number (65780896).

Almost surely, 2^131561791 is an apocalyptic number.

131561791 is a deficient number, since it is larger than the sum of its proper divisors (1).

131561791 is an equidigital number, since it uses as much as digits as its factorization.

131561791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5670, while the sum is 34.

The square root of 131561791 is about 11470.0388403876. The cubic root of 131561791 is about 508.6002769817.

The spelling of 131561791 in words is "one hundred thirty-one million, five hundred sixty-one thousand, seven hundred ninety-one".