78678673 has 2 divisors, whose sum is σ = 78678674. Its totient is φ = 78678672.

The previous prime is 78678667. The next prime is 78678679. The reversal of 78678673 is 37687687.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (78678667) and next prime (78678679).

It can be written as a sum of positive squares in only one way, i.e., 78641424 + 37249 = 8868^2 + 193^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78678673 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78678673.

It is not a weakly prime, because it can be changed into another prime (78678679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39339336 + 39339337.

It is an arithmetic number, because the mean of its divisors is an integer number (39339337).

Almost surely, 2^78678673 is an apocalyptic number.

It is an amenable number.

78678673 is a deficient number, since it is larger than the sum of its proper divisors (1).

78678673 is an equidigital number, since it uses as much as digits as its factorization.

78678673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2370816, while the sum is 52.

The square root of 78678673 is about 8870.0999430672. The cubic root of 78678673 is about 428.5014956739.

The spelling of 78678673 in words is "seventy-eight million, six hundred seventy-eight thousand, six hundred seventy-three".