18155180497 has 2 divisors, whose sum is σ = 18155180498. Its totient is φ = 18155180496.

The previous prime is 18155180441. The next prime is 18155180509. The reversal of 18155180497 is 79408155181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18106124481 + 49056016 = 134559^2 + 7004^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18155180497 is a prime.

It is a super-2 number, since 2×18155180497² (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 18155180497.

It is not a weakly prime, because it can be changed into another prime (18155184497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9077590248 + 9077590249.

It is an arithmetic number, because the mean of its divisors is an integer number (9077590249).

Almost surely, 2^18155180497 is an apocalyptic number.

It is an amenable number.

18155180497 is a deficient number, since it is larger than the sum of its proper divisors (1).

18155180497 is an equidigital number, since it uses as much as digits as its factorization.

18155180497 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 403200, while the sum is 49.

The spelling of 18155180497 in words is "eighteen billion, one hundred fifty-five million, one hundred eighty thousand, four hundred ninety-seven".