9115172509 has 4 divisors (see below), whose sum is σ = 9133081020. Its totient is φ = 9097264000.

The previous prime is 9115172453. The next prime is 9115172567. The reversal of 9115172509 is 9052715119.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9052715119 = 7 ⋅1293245017.

It can be written as a sum of positive squares in 2 ways, for example, as 6488302500 + 2626870009 = 80550^2 + 51253^2 .

It is a cyclic number.

It is not a de Polignac number, because 9115172509 - 2¹¹ = 9115170461 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9115172569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8953492 + ... + 8954509.

It is an arithmetic number, because the mean of its divisors is an integer number (2283270255).

Almost surely, 2^9115172509 is an apocalyptic number.

It is an amenable number.

9115172509 is a deficient number, since it is larger than the sum of its proper divisors (17908511).

9115172509 is a wasteful number, since it uses less digits than its factorization.

9115172509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17908510.

The product of its (nonzero) digits is 28350, while the sum is 40.

The square root of 9115172509 is about 95473.4125764864. The cubic root of 9115172509 is about 2088.9191475611.

The spelling of 9115172509 in words is "nine billion, one hundred fifteen million, one hundred seventy-two thousand, five hundred nine".