78817247 has 2 divisors, whose sum is σ = 78817248. Its totient is φ = 78817246.

The previous prime is 78817229. The next prime is 78817267. The reversal of 78817247 is 74271887.

It is a weak prime.

It is an emirp because it is prime and its reverse (74271887) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78817247 - 2¹⁴ = 78800863 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 78817198 and 78817207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78817217) 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, 39408623 + 39408624.

It is an arithmetic number, because the mean of its divisors is an integer number (39408624).

Almost surely, 2^78817247 is an apocalyptic number.

78817247 is a deficient number, since it is larger than the sum of its proper divisors (1).

78817247 is an equidigital number, since it uses as much as digits as its factorization.

78817247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 175616, while the sum is 44.

The square root of 78817247 is about 8877.9078053334. The cubic root of 78817247 is about 428.7529163670.

The spelling of 78817247 in words is "seventy-eight million, eight hundred seventeen thousand, two hundred forty-seven".