78739247 has 2 divisors, whose sum is σ = 78739248. Its totient is φ = 78739246.

The previous prime is 78739231. The next prime is 78739289. The reversal of 78739247 is 74293787.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78739247 - 2⁴ = 78739231 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78739207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39369623 + 39369624.

It is an arithmetic number, because the mean of its divisors is an integer number (39369624).

Almost surely, 2^78739247 is an apocalyptic number.

78739247 is a deficient number, since it is larger than the sum of its proper divisors (1).

78739247 is an equidigital number, since it uses as much as digits as its factorization.

78739247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 592704, while the sum is 47.

The square root of 78739247 is about 8873.5137910526. The cubic root of 78739247 is about 428.6114339428.

The spelling of 78739247 in words is "seventy-eight million, seven hundred thirty-nine thousand, two hundred forty-seven".