1318216217 has 4 divisors (see below), whose sum is σ = 1318539300. Its totient is φ = 1317893136.

The previous prime is 1318216201. The next prime is 1318216301. The reversal of 1318216217 is 7126128131.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 800380681 + 517835536 = 28291^2 + 22756^2 .

It is a cyclic number.

It is not a de Polignac number, because 1318216217 - 2⁴ = 1318216201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1318210217) 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 in 3 ways as a sum of consecutive naturals, for example, 155342 + ... + 163607.

It is an arithmetic number, because the mean of its divisors is an integer number (329634825).

Almost surely, 2^1318216217 is an apocalyptic number.

It is an amenable number.

1318216217 is a deficient number, since it is larger than the sum of its proper divisors (323083).

1318216217 is an equidigital number, since it uses as much as digits as its factorization.

1318216217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323082.

The product of its digits is 4032, while the sum is 32.

The square root of 1318216217 is about 36307.2474445530. The cubic root of 1318216217 is about 1096.4669612405.

The spelling of 1318216217 in words is "one billion, three hundred eighteen million, two hundred sixteen thousand, two hundred seventeen".