9909517157 has 2 divisors, whose sum is σ = 9909517158. Its totient is φ = 9909517156.

The previous prime is 9909517117. The next prime is 9909517169. The reversal of 9909517157 is 7517159099.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8698546756 + 1210970401 = 93266^2 + 34799^2 .

It is an emirp because it is prime and its reverse (7517159099) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9909517157 - 2²⁶ = 9842408293 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 9909517099 and 9909517108.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9909517117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4954758578 + 4954758579.

It is an arithmetic number, because the mean of its divisors is an integer number (4954758579).

Almost surely, 2^9909517157 is an apocalyptic number.

It is an amenable number.

9909517157 is a deficient number, since it is larger than the sum of its proper divisors (1).

9909517157 is an equidigital number, since it uses as much as digits as its factorization.

9909517157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 893025, while the sum is 53.

The square root of 9909517157 is about 99546.5577355641. The cubic root of 9909517157 is about 2147.9170132005.

The spelling of 9909517157 in words is "nine billion, nine hundred nine million, five hundred seventeen thousand, one hundred fifty-seven".