11815172503 has 4 divisors (see below), whose sum is σ = 12066559200. Its totient is φ = 11563785808.

The previous prime is 11815172497. The next prime is 11815172513. The reversal of 11815172503 is 30527151811.

11815172503 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30527151811 = 13 ⋅2348242447.

It is a cyclic number.

It is not a de Polignac number, because 11815172503 - 2¹⁷ = 11815041431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11815172513) 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 in 3 ways as a sum of consecutive naturals, for example, 125693278 + ... + 125693371.

It is an arithmetic number, because the mean of its divisors is an integer number (3016639800).

Almost surely, 2^11815172503 is an apocalyptic number.

11815172503 is a deficient number, since it is larger than the sum of its proper divisors (251386697).

11815172503 is an equidigital number, since it uses as much as digits as its factorization.

11815172503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251386696.

The product of its (nonzero) digits is 8400, while the sum is 34.

The spelling of 11815172503 in words is "eleven billion, eight hundred fifteen million, one hundred seventy-two thousand, five hundred three".