78864913 has 2 divisors, whose sum is σ = 78864914. Its totient is φ = 78864912.

The previous prime is 78864889. The next prime is 78864917. The reversal of 78864913 is 31946887.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46009089 + 32855824 = 6783^2 + 5732^2 .

It is a cyclic number.

It is not a de Polignac number, because 78864913 - 2²⁵ = 45310481 is a prime.

It is not a weakly prime, because it can be changed into another prime (78864917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39432456 + 39432457.

It is an arithmetic number, because the mean of its divisors is an integer number (39432457).

Almost surely, 2^78864913 is an apocalyptic number.

It is an amenable number.

78864913 is a deficient number, since it is larger than the sum of its proper divisors (1).

78864913 is an equidigital number, since it uses as much as digits as its factorization.

78864913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 46.

The square root of 78864913 is about 8880.5919284696. The cubic root of 78864913 is about 428.8393306939.

The spelling of 78864913 in words is "seventy-eight million, eight hundred sixty-four thousand, nine hundred thirteen".