8478740742217 has 2 divisors, whose sum is σ = 8478740742218. Its totient is φ = 8478740742216.

The previous prime is 8478740742179. The next prime is 8478740742221. The reversal of 8478740742217 is 7122470478748.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6169605209161 + 2309135533056 = 2483869^2 + 1519584^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8478740742217 is a prime.

It is not a weakly prime, because it can be changed into another prime (8478740742247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4239370371108 + 4239370371109.

It is an arithmetic number, because the mean of its divisors is an integer number (4239370371109).

Almost surely, 2^{8478740742217} is an apocalyptic number.

It is an amenable number.

8478740742217 is a deficient number, since it is larger than the sum of its proper divisors (1).

8478740742217 is an equidigital number, since it uses as much as digits as its factorization.

8478740742217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39337984, while the sum is 61.

The spelling of 8478740742217 in words is "eight trillion, four hundred seventy-eight billion, seven hundred forty million, seven hundred forty-two thousand, two hundred seventeen".