78434729 has 2 divisors, whose sum is σ = 78434730. Its totient is φ = 78434728.

The previous prime is 78434711. The next prime is 78434737. The reversal of 78434729 is 92743487.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78234025 + 200704 = 8845^2 + 448^2 .

It is an emirp because it is prime and its reverse (92743487) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78434729 - 2¹² = 78430633 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 78434729.

It is not a weakly prime, because it can be changed into another prime (78434029) 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, 39217364 + 39217365.

It is an arithmetic number, because the mean of its divisors is an integer number (39217365).

Almost surely, 2^78434729 is an apocalyptic number.

It is an amenable number.

78434729 is a deficient number, since it is larger than the sum of its proper divisors (1).

78434729 is an equidigital number, since it uses as much as digits as its factorization.

78434729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 44.

The square root of 78434729 is about 8856.3383517117. The cubic root of 78434729 is about 428.0581794874.

The spelling of 78434729 in words is "seventy-eight million, four hundred thirty-four thousand, seven hundred twenty-nine".