18540818503 has 2 divisors, whose sum is σ = 18540818504. Its totient is φ = 18540818502.

The previous prime is 18540818497. The next prime is 18540818531. The reversal of 18540818503 is 30581804581.

It is a weak prime.

It is an emirp because it is prime and its reverse (30581804581) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18540818503 - 2⁹ = 18540817991 is a prime.

It is a super-2 number, since 2×18540818503² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18540818503.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18540818563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9270409251 + 9270409252.

It is an arithmetic number, because the mean of its divisors is an integer number (9270409252).

Almost surely, 2^18540818503 is an apocalyptic number.

18540818503 is a deficient number, since it is larger than the sum of its proper divisors (1).

18540818503 is an equidigital number, since it uses as much as digits as its factorization.

18540818503 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 153600, while the sum is 43.

The spelling of 18540818503 in words is "eighteen billion, five hundred forty million, eight hundred eighteen thousand, five hundred three".