78809708969 has 2 divisors, whose sum is σ = 78809708970. Its totient is φ = 78809708968.

The previous prime is 78809708951. The next prime is 78809709007. The reversal of 78809708969 is 96980790887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59401875625 + 19407833344 = 243725^2 + 139312^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78809708969 is a prime.

It is a super-2 number, since 2×78809708969² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78802708969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39404854484 + 39404854485.

It is an arithmetic number, because the mean of its divisors is an integer number (39404854485).

Almost surely, 2^78809708969 is an apocalyptic number.

It is an amenable number.

78809708969 is a deficient number, since it is larger than the sum of its proper divisors (1).

78809708969 is an equidigital number, since it uses as much as digits as its factorization.

78809708969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 109734912, while the sum is 71.

The spelling of 78809708969 in words is "seventy-eight billion, eight hundred nine million, seven hundred eight thousand, nine hundred sixty-nine".