78997156243 has 2 divisors, whose sum is σ = 78997156244. Its totient is φ = 78997156242.

The previous prime is 78997156219. The next prime is 78997156279. The reversal of 78997156243 is 34265179987.

It is a weak prime.

It is an emirp because it is prime and its reverse (34265179987) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78997156243 - 2¹³ = 78997148051 is a prime.

It is not a weakly prime, because it can be changed into another prime (78997157243) 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, 39498578121 + 39498578122.

It is an arithmetic number, because the mean of its divisors is an integer number (39498578122).

Almost surely, 2^78997156243 is an apocalyptic number.

78997156243 is a deficient number, since it is larger than the sum of its proper divisors (1).

78997156243 is an equidigital number, since it uses as much as digits as its factorization.

78997156243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22861440, while the sum is 61.

The spelling of 78997156243 in words is "seventy-eight billion, nine hundred ninety-seven million, one hundred fifty-six thousand, two hundred forty-three".