78985321 has 2 divisors, whose sum is σ = 78985322. Its totient is φ = 78985320.

The previous prime is 78985307. The next prime is 78985327. The reversal of 78985321 is 12358987.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60279696 + 18705625 = 7764^2 + 4325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78985321 is a prime.

It is not a weakly prime, because it can be changed into another prime (78985327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39492660 + 39492661.

It is an arithmetic number, because the mean of its divisors is an integer number (39492661).

Almost surely, 2^78985321 is an apocalyptic number.

It is an amenable number.

78985321 is a deficient number, since it is larger than the sum of its proper divisors (1).

78985321 is an equidigital number, since it uses as much as digits as its factorization.

78985321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 43.

The square root of 78985321 is about 8887.3686206886. The cubic root of 78985321 is about 429.0574650030.

The spelling of 78985321 in words is "seventy-eight million, nine hundred eighty-five thousand, three hundred twenty-one".