78999959 has 2 divisors, whose sum is σ = 78999960. Its totient is φ = 78999958.

The previous prime is 78999937. The next prime is 78999961. The reversal of 78999959 is 95999987.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78999959 - 2²⁰ = 77951383 is a prime.

Together with 78999961, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 78999895 and 78999904.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78999979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39499979 + 39499980.

It is an arithmetic number, because the mean of its divisors is an integer number (39499980).

Almost surely, 2^78999959 is an apocalyptic number.

78999959 is a deficient number, since it is larger than the sum of its proper divisors (1).

78999959 is an equidigital number, since it uses as much as digits as its factorization.

78999959 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16533720, while the sum is 65.

The square root of 78999959 is about 8888.1921108851. The cubic root of 78999959 is about 429.0839684729.

The spelling of 78999959 in words is "seventy-eight million, nine hundred ninety-nine thousand, nine hundred fifty-nine".