78704626409 has 2 divisors, whose sum is σ = 78704626410. Its totient is φ = 78704626408.

The previous prime is 78704626379. The next prime is 78704626411. The reversal of 78704626409 is 90462640787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66605286400 + 12099340009 = 258080^2 + 109997^2 .

It is a cyclic number.

It is not a de Polignac number, because 78704626409 - 2²⁸ = 78436190953 is a prime.

Together with 78704626411, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78704626909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39352313204 + 39352313205.

It is an arithmetic number, because the mean of its divisors is an integer number (39352313205).

Almost surely, 2^78704626409 is an apocalyptic number.

It is an amenable number.

78704626409 is a deficient number, since it is larger than the sum of its proper divisors (1).

78704626409 is an equidigital number, since it uses as much as digits as its factorization.

78704626409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4064256, while the sum is 53.

The spelling of 78704626409 in words is "seventy-eight billion, seven hundred four million, six hundred twenty-six thousand, four hundred nine".