78986993 has 2 divisors, whose sum is σ = 78986994. Its totient is φ = 78986992.

The previous prime is 78986989. The next prime is 78987019. The reversal of 78986993 is 39968987.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75829264 + 3157729 = 8708^2 + 1777^2 .

It is an emirp because it is prime and its reverse (39968987) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78986993 - 2² = 78986989 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78986893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39493496 + 39493497.

It is an arithmetic number, because the mean of its divisors is an integer number (39493497).

Almost surely, 2^78986993 is an apocalyptic number.

It is an amenable number.

78986993 is a deficient number, since it is larger than the sum of its proper divisors (1).

78986993 is an equidigital number, since it uses as much as digits as its factorization.

78986993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5878656, while the sum is 59.

The square root of 78986993 is about 8887.4626862789. The cubic root of 78986993 is about 429.0604924812.

The spelling of 78986993 in words is "seventy-eight million, nine hundred eighty-six thousand, nine hundred ninety-three".