78842879 has 2 divisors, whose sum is σ = 78842880. Its totient is φ = 78842878.

The previous prime is 78842857. The next prime is 78842887. The reversal of 78842879 is 97824887.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78842879 is a prime.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 78842879.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78842809) 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, 39421439 + 39421440.

It is an arithmetic number, because the mean of its divisors is an integer number (39421440).

Almost surely, 2^78842879 is an apocalyptic number.

78842879 is a deficient number, since it is larger than the sum of its proper divisors (1).

78842879 is an equidigital number, since it uses as much as digits as its factorization.

78842879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1806336, while the sum is 53.

The square root of 78842879 is about 8879.3512713486. The cubic root of 78842879 is about 428.7993892904.

The spelling of 78842879 in words is "seventy-eight million, eight hundred forty-two thousand, eight hundred seventy-nine".