1317218649 has 4 divisors (see below), whose sum is σ = 1756291536. Its totient is φ = 878145764.

The previous prime is 1317218641. The next prime is 1317218677. The reversal of 1317218649 is 9468127131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1317218649 - 2³ = 1317218641 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1317218649.

It is not an unprimeable number, because it can be changed into a prime (1317218641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219536439 + ... + 219536444.

It is an arithmetic number, because the mean of its divisors is an integer number (439072884).

Almost surely, 2^1317218649 is an apocalyptic number.

It is an amenable number.

1317218649 is a deficient number, since it is larger than the sum of its proper divisors (439072887).

1317218649 is an equidigital number, since it uses as much as digits as its factorization.

1317218649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439072886.

The product of its digits is 72576, while the sum is 42.

The square root of 1317218649 is about 36293.5069812770. The cubic root of 1317218649 is about 1096.1903054667.

The spelling of 1317218649 in words is "one billion, three hundred seventeen million, two hundred eighteen thousand, six hundred forty-nine".