1290255761 has 2 divisors, whose sum is σ = 1290255762. Its totient is φ = 1290255760.

The previous prime is 1290255727. The next prime is 1290255767. The reversal of 1290255761 is 1675520921.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 956974225 + 333281536 = 30935^2 + 18256^2 .

It is a cyclic number.

It is not a de Polignac number, because 1290255761 - 2⁶ = 1290255697 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1290255767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645127880 + 645127881.

It is an arithmetic number, because the mean of its divisors is an integer number (645127881).

Almost surely, 2^1290255761 is an apocalyptic number.

It is an amenable number.

1290255761 is a deficient number, since it is larger than the sum of its proper divisors (1).

1290255761 is an equidigital number, since it uses as much as digits as its factorization.

1290255761 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 37800, while the sum is 38.

The square root of 1290255761 is about 35920.1303032158. The cubic root of 1290255761 is about 1088.6591713758.

The spelling of 1290255761 in words is "one billion, two hundred ninety million, two hundred fifty-five thousand, seven hundred sixty-one".