131051561 has 2 divisors, whose sum is σ = 131051562. Its totient is φ = 131051560.

The previous prime is 131051527. The next prime is 131051579. The reversal of 131051561 is 165150131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92064025 + 38987536 = 9595^2 + 6244^2 .

It is an emirp because it is prime and its reverse (165150131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131051561 - 2⁶ = 131051497 is a prime.

It is not a weakly prime, because it can be changed into another prime (131051581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65525780 + 65525781.

It is an arithmetic number, because the mean of its divisors is an integer number (65525781).

Almost surely, 2^131051561 is an apocalyptic number.

It is an amenable number.

131051561 is a deficient number, since it is larger than the sum of its proper divisors (1).

131051561 is an equidigital number, since it uses as much as digits as its factorization.

131051561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 450, while the sum is 23.

The square root of 131051561 is about 11447.7753734077. The cubic root of 131051561 is about 507.9419315381.

The spelling of 131051561 in words is "one hundred thirty-one million, fifty-one thousand, five hundred sixty-one".