78644140067 has 2 divisors, whose sum is σ = 78644140068. Its totient is φ = 78644140066.

The previous prime is 78644140021. The next prime is 78644140117. The reversal of 78644140067 is 76004144687.

It is a weak prime.

It is an emirp because it is prime and its reverse (76004144687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78644140067 - 2²⁰ = 78643091491 is a prime.

It is not a weakly prime, because it can be changed into another prime (78644146067) 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, 39322070033 + 39322070034.

It is an arithmetic number, because the mean of its divisors is an integer number (39322070034).

Almost surely, 2^78644140067 is an apocalyptic number.

78644140067 is a deficient number, since it is larger than the sum of its proper divisors (1).

78644140067 is an equidigital number, since it uses as much as digits as its factorization.

78644140067 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 903168, while the sum is 47.

The spelling of 78644140067 in words is "seventy-eight billion, six hundred forty-four million, one hundred forty thousand, sixty-seven".