261742727247137 has 2 divisors, whose sum is σ = 261742727247138. Its totient is φ = 261742727247136.

The previous prime is 261742727247073. The next prime is 261742727247229. The reversal of 261742727247137 is 731742727247162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 148045525420816 + 113697201826321 = 12167396^2 + 10662889^2 .

It is a cyclic number.

It is not a de Polignac number, because 261742727247137 - 2⁶ = 261742727247073 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 261742727247137.

It is not a weakly prime, because it can be changed into another prime (261742727277137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130871363623568 + 130871363623569.

It is an arithmetic number, because the mean of its divisors is an integer number (130871363623569).

Almost surely, 2^{261742727247137} is an apocalyptic number.

It is an amenable number.

261742727247137 is a deficient number, since it is larger than the sum of its proper divisors (1).

261742727247137 is an equidigital number, since it uses as much as digits as its factorization.

261742727247137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77446656, while the sum is 62.

The spelling of 261742727247137 in words is "two hundred sixty-one trillion, seven hundred forty-two billion, seven hundred twenty-seven million, two hundred forty-seven thousand, one hundred thirty-seven".