775662661 has 2 divisors, whose sum is σ = 775662662. Its totient is φ = 775662660.

The previous prime is 775662653. The next prime is 775662677. The reversal of 775662661 is 166266577.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 766237761 + 9424900 = 27681^2 + 3070^2 .

It is a cyclic number.

It is not a de Polignac number, because 775662661 - 2³ = 775662653 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (775662161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 387831330 + 387831331.

It is an arithmetic number, because the mean of its divisors is an integer number (387831331).

Almost surely, 2^775662661 is an apocalyptic number.

It is an amenable number.

775662661 is a deficient number, since it is larger than the sum of its proper divisors (1).

775662661 is an equidigital number, since it uses as much as digits as its factorization.

775662661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 635040, while the sum is 46.

The square root of 775662661 is about 27850.7210140061. The cubic root of 775662661 is about 918.8070000516.

The spelling of 775662661 in words is "seven hundred seventy-five million, six hundred sixty-two thousand, six hundred sixty-one".