1218395441 has 2 divisors, whose sum is σ = 1218395442. Its totient is φ = 1218395440.

The previous prime is 1218395383. The next prime is 1218395447. The reversal of 1218395441 is 1445938121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 956603041 + 261792400 = 30929^2 + 16180^2 .

It is an emirp because it is prime and its reverse (1445938121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1218395441 - 2⁶ = 1218395377 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1218395395 and 1218395404.

It is not a weakly prime, because it can be changed into another prime (1218395447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609197720 + 609197721.

It is an arithmetic number, because the mean of its divisors is an integer number (609197721).

Almost surely, 2^1218395441 is an apocalyptic number.

It is an amenable number.

1218395441 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218395441 is an equidigital number, since it uses as much as digits as its factorization.

1218395441 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 38.

The square root of 1218395441 is about 34905.5216405657. The cubic root of 1218395441 is about 1068.0610768163.

The spelling of 1218395441 in words is "one billion, two hundred eighteen million, three hundred ninety-five thousand, four hundred forty-one".