1218517938247 has 2 divisors, whose sum is σ = 1218517938248. Its totient is φ = 1218517938246.

The previous prime is 1218517938181. The next prime is 1218517938263. The reversal of 1218517938247 is 7428397158121.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1218517938247 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1218517938191 and 1218517938200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1218517948247) 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, 609258969123 + 609258969124.

It is an arithmetic number, because the mean of its divisors is an integer number (609258969124).

Almost surely, 2^{1218517938247} is an apocalyptic number.

1218517938247 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218517938247 is an equidigital number, since it uses as much as digits as its factorization.

1218517938247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6773760, while the sum is 58.

The spelling of 1218517938247 in words is "one trillion, two hundred eighteen billion, five hundred seventeen million, nine hundred thirty-eight thousand, two hundred forty-seven".