1218889057 has 2 divisors, whose sum is σ = 1218889058. Its totient is φ = 1218889056.

The previous prime is 1218889043. The next prime is 1218889081. The reversal of 1218889057 is 7509888121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 740329681 + 478559376 = 27209^2 + 21876^2 .

It is an emirp because it is prime and its reverse (7509888121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1218889057 - 2¹¹ = 1218887009 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1218889057.

It is not a weakly prime, because it can be changed into another prime (1218889037) 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, 609444528 + 609444529.

It is an arithmetic number, because the mean of its divisors is an integer number (609444529).

Almost surely, 2^1218889057 is an apocalyptic number.

It is an amenable number.

1218889057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218889057 is an equidigital number, since it uses as much as digits as its factorization.

1218889057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 322560, while the sum is 49.

The square root of 1218889057 is about 34912.5916683365. The cubic root of 1218889057 is about 1068.2052940486.

The spelling of 1218889057 in words is "one billion, two hundred eighteen million, eight hundred eighty-nine thousand, fifty-seven".