78940859 has 2 divisors, whose sum is σ = 78940860. Its totient is φ = 78940858.

The previous prime is 78940847. The next prime is 78940909. The reversal of 78940859 is 95804987.

It is an a-pointer prime, because the next prime (78940909) can be obtained adding 78940859 to its sum of digits (50).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78940859 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78940259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39470429 + 39470430.

It is an arithmetic number, because the mean of its divisors is an integer number (39470430).

Almost surely, 2^78940859 is an apocalyptic number.

78940859 is a deficient number, since it is larger than the sum of its proper divisors (1).

78940859 is an equidigital number, since it uses as much as digits as its factorization.

78940859 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 725760, while the sum is 50.

The square root of 78940859 is about 8884.8668532511. The cubic root of 78940859 is about 428.9769423041.

The spelling of 78940859 in words is "seventy-eight million, nine hundred forty thousand, eight hundred fifty-nine".