9717842557 has 2 divisors, whose sum is σ = 9717842558. Its totient is φ = 9717842556.

The previous prime is 9717842513. The next prime is 9717842579. The reversal of 9717842557 is 7552487179.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8197310521 + 1520532036 = 90539^2 + 38994^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9717842557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 9717842498 and 9717842507.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9717842257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4858921278 + 4858921279.

It is an arithmetic number, because the mean of its divisors is an integer number (4858921279).

Almost surely, 2^9717842557 is an apocalyptic number.

It is an amenable number.

9717842557 is a deficient number, since it is larger than the sum of its proper divisors (1).

9717842557 is an equidigital number, since it uses as much as digits as its factorization.

9717842557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4939200, while the sum is 55.

The square root of 9717842557 is about 98579.1182604105. The cubic root of 9717842557 is about 2133.9780740029.

The spelling of 9717842557 in words is "nine billion, seven hundred seventeen million, eight hundred forty-two thousand, five hundred fifty-seven".