78649339 has 2 divisors, whose sum is σ = 78649340. Its totient is φ = 78649338.

The previous prime is 78649321. The next prime is 78649367. The reversal of 78649339 is 93394687.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78649339 - 2¹⁹ = 78125051 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78649292 and 78649301.

It is not a weakly prime, because it can be changed into another prime (78649369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39324669 + 39324670.

It is an arithmetic number, because the mean of its divisors is an integer number (39324670).

Almost surely, 2^78649339 is an apocalyptic number.

78649339 is a deficient number, since it is larger than the sum of its proper divisors (1).

78649339 is an equidigital number, since it uses as much as digits as its factorization.

78649339 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 49.

The square root of 78649339 is about 8868.4462562503. The cubic root of 78649339 is about 428.4482358986.

The spelling of 78649339 in words is "seventy-eight million, six hundred forty-nine thousand, three hundred thirty-nine".