78690757 has 2 divisors, whose sum is σ = 78690758. Its totient is φ = 78690756.

The previous prime is 78690709. The next prime is 78690779. The reversal of 78690757 is 75709687.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39765636 + 38925121 = 6306^2 + 6239^2 .

It is a cyclic number.

It is not a de Polignac number, because 78690757 - 2²³ = 70302149 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78690757.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78691757) 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, 39345378 + 39345379.

It is an arithmetic number, because the mean of its divisors is an integer number (39345379).

Almost surely, 2^78690757 is an apocalyptic number.

It is an amenable number.

78690757 is a deficient number, since it is larger than the sum of its proper divisors (1).

78690757 is an equidigital number, since it uses as much as digits as its factorization.

78690757 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 740880, while the sum is 49.

The square root of 78690757 is about 8870.7810817312. The cubic root of 78690757 is about 428.5234319318.

The spelling of 78690757 in words is "seventy-eight million, six hundred ninety thousand, seven hundred fifty-seven".