1266807761 has 2 divisors, whose sum is σ = 1266807762. Its totient is φ = 1266807760.

The previous prime is 1266807757. The next prime is 1266807769. The reversal of 1266807761 is 1677086621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 798345025 + 468462736 = 28255^2 + 21644^2 .

It is a cyclic number.

It is not a de Polignac number, because 1266807761 - 2² = 1266807757 is a prime.

It is not a weakly prime, because it can be changed into another prime (1266807769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 633403880 + 633403881.

It is an arithmetic number, because the mean of its divisors is an integer number (633403881).

Almost surely, 2^1266807761 is an apocalyptic number.

It is an amenable number.

1266807761 is a deficient number, since it is larger than the sum of its proper divisors (1).

1266807761 is an equidigital number, since it uses as much as digits as its factorization.

1266807761 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 1266807761 is about 35592.2429891683. The cubic root of 1266807761 is about 1082.0240281871.

The spelling of 1266807761 in words is "one billion, two hundred sixty-six million, eight hundred seven thousand, seven hundred sixty-one".