1218674749549 has 2 divisors, whose sum is σ = 1218674749550. Its totient is φ = 1218674749548.

The previous prime is 1218674749489. The next prime is 1218674749559. The reversal of 1218674749549 is 9459474768121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1111495775625 + 107178973924 = 1054275^2 + 327382^2 .

It is a cyclic number.

It is not a de Polignac number, because 1218674749549 - 2⁹ = 1218674749037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1218674749559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609337374774 + 609337374775.

It is an arithmetic number, because the mean of its divisors is an integer number (609337374775).

Almost surely, 2^{1218674749549} is an apocalyptic number.

It is an amenable number.

1218674749549 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218674749549 is an equidigital number, since it uses as much as digits as its factorization.

1218674749549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 121927680, while the sum is 67.

The spelling of 1218674749549 in words is "one trillion, two hundred eighteen billion, six hundred seventy-four million, seven hundred forty-nine thousand, five hundred forty-nine".