78997967 has 2 divisors, whose sum is σ = 78997968. Its totient is φ = 78997966.

The previous prime is 78997957. The next prime is 78997969. The reversal of 78997967 is 76979987.

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-78997967 is a prime.

Together with 78997969, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78997969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39498983 + 39498984.

It is an arithmetic number, because the mean of its divisors is an integer number (39498984).

Almost surely, 2^78997967 is an apocalyptic number.

78997967 is a deficient number, since it is larger than the sum of its proper divisors (1).

78997967 is an equidigital number, since it uses as much as digits as its factorization.

78997967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12002256, while the sum is 62.

The square root of 78997967 is about 8888.0800513947. The cubic root of 78997967 is about 429.0803619628.

The spelling of 78997967 in words is "seventy-eight million, nine hundred ninety-seven thousand, nine hundred sixty-seven".