78899993 has 2 divisors, whose sum is σ = 78899994. Its totient is φ = 78899992.

The previous prime is 78899983. The next prime is 78900001. The reversal of 78899993 is 39999887.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77915929 + 984064 = 8827^2 + 992^2 .

It is a cyclic number.

It is not a de Polignac number, because 78899993 - 2¹⁰ = 78898969 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78899903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39449996 + 39449997.

It is an arithmetic number, because the mean of its divisors is an integer number (39449997).

Almost surely, 2^78899993 is an apocalyptic number.

It is an amenable number.

78899993 is a deficient number, since it is larger than the sum of its proper divisors (1).

78899993 is an equidigital number, since it uses as much as digits as its factorization.

78899993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8817984, while the sum is 62.

The square root of 78899993 is about 8882.5668024507. The cubic root of 78899993 is about 428.9029054539.

The spelling of 78899993 in words is "seventy-eight million, eight hundred ninety-nine thousand, nine hundred ninety-three".