1218794149 has 2 divisors, whose sum is σ = 1218794150. Its totient is φ = 1218794148.

The previous prime is 1218794113. The next prime is 1218794153. The reversal of 1218794149 is 9414978121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1204784100 + 14010049 = 34710^2 + 3743^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1218794149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1218794099 and 1218794108.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1218794179) 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, 609397074 + 609397075.

It is an arithmetic number, because the mean of its divisors is an integer number (609397075).

Almost surely, 2^1218794149 is an apocalyptic number.

It is an amenable number.

1218794149 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218794149 is an equidigital number, since it uses as much as digits as its factorization.

1218794149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 46.

The square root of 1218794149 is about 34911.2324188076. The cubic root of 1218794149 is about 1068.1775682932.

The spelling of 1218794149 in words is "one billion, two hundred eighteen million, seven hundred ninety-four thousand, one hundred forty-nine".