78740393 has 2 divisors, whose sum is σ = 78740394. Its totient is φ = 78740392.

The previous prime is 78740383. The next prime is 78740407. The reversal of 78740393 is 39304787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77915929 + 824464 = 8827^2 + 908^2 .

It is a cyclic number.

It is not a de Polignac number, because 78740393 - 2¹⁸ = 78478249 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78740393.

It is not a weakly prime, because it can be changed into another prime (78740383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39370196 + 39370197.

It is an arithmetic number, because the mean of its divisors is an integer number (39370197).

Almost surely, 2^78740393 is an apocalyptic number.

It is an amenable number.

78740393 is a deficient number, since it is larger than the sum of its proper divisors (1).

78740393 is an equidigital number, since it uses as much as digits as its factorization.

78740393 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 127008, while the sum is 41.

The square root of 78740393 is about 8873.5783650115. The cubic root of 78740393 is about 428.6135133223.

The spelling of 78740393 in words is "seventy-eight million, seven hundred forty thousand, three hundred ninety-three".