810768649 has 2 divisors, whose sum is σ = 810768650. Its totient is φ = 810768648.

The previous prime is 810768611. The next prime is 810768671. The reversal of 810768649 is 946867018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 720385600 + 90383049 = 26840^2 + 9507^2 .

It is a cyclic number.

It is not a de Polignac number, because 810768649 - 2⁹ = 810768137 is a prime.

It is not a weakly prime, because it can be changed into another prime (810768349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405384324 + 405384325.

It is an arithmetic number, because the mean of its divisors is an integer number (405384325).

Almost surely, 2^810768649 is an apocalyptic number.

It is an amenable number.

810768649 is a deficient number, since it is larger than the sum of its proper divisors (1).

810768649 is an equidigital number, since it uses as much as digits as its factorization.

810768649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 580608, while the sum is 49.

The square root of 810768649 is about 28473.9995258833. Note that the first 3 decimals coincide. The cubic root of 810768649 is about 932.4645192029.

The spelling of 810768649 in words is "eight hundred ten million, seven hundred sixty-eight thousand, six hundred forty-nine".