77964036809 has 2 divisors, whose sum is σ = 77964036810. Its totient is φ = 77964036808.

The previous prime is 77964036797. The next prime is 77964036833. The reversal of 77964036809 is 90863046977.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67874838784 + 10089198025 = 260528^2 + 100445^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77964036809 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 (77964036869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38982018404 + 38982018405.

It is an arithmetic number, because the mean of its divisors is an integer number (38982018405).

Almost surely, 2^77964036809 is an apocalyptic number.

It is an amenable number.

77964036809 is a deficient number, since it is larger than the sum of its proper divisors (1).

77964036809 is an equidigital number, since it uses as much as digits as its factorization.

77964036809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13716864, while the sum is 59.

The spelling of 77964036809 in words is "seventy-seven billion, nine hundred sixty-four million, thirty-six thousand, eight hundred nine".