78785929 has 2 divisors, whose sum is σ = 78785930. Its totient is φ = 78785928.

The previous prime is 78785909. The next prime is 78785947. The reversal of 78785929 is 92958787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69755904 + 9030025 = 8352^2 + 3005^2 .

It is an emirp because it is prime and its reverse (92958787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78785929 - 2⁷ = 78785801 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78785929.

It is not a weakly prime, because it can be changed into another prime (78785909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39392964 + 39392965.

It is an arithmetic number, because the mean of its divisors is an integer number (39392965).

Almost surely, 2^78785929 is an apocalyptic number.

It is an amenable number.

78785929 is a deficient number, since it is larger than the sum of its proper divisors (1).

78785929 is an equidigital number, since it uses as much as digits as its factorization.

78785929 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2540160, while the sum is 55.

The square root of 78785929 is about 8876.1438136164. The cubic root of 78785929 is about 428.6961205800.

The spelling of 78785929 in words is "seventy-eight million, seven hundred eighty-five thousand, nine hundred twenty-nine".