78748639 has 2 divisors, whose sum is σ = 78748640. Its totient is φ = 78748638.

The previous prime is 78748627. The next prime is 78748661. The reversal of 78748639 is 93684787.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78748639 - 2⁹ = 78748127 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78748669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39374319 + 39374320.

It is an arithmetic number, because the mean of its divisors is an integer number (39374320).

Almost surely, 2^78748639 is an apocalyptic number.

78748639 is a deficient number, since it is larger than the sum of its proper divisors (1).

78748639 is an equidigital number, since it uses as much as digits as its factorization.

78748639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2032128, while the sum is 52.

The square root of 78748639 is about 8874.0429906554. The cubic root of 78748639 is about 428.6284748243.

The spelling of 78748639 in words is "seventy-eight million, seven hundred forty-eight thousand, six hundred thirty-nine".