1218317516815 has 16 divisors (see below), whose sum is σ = 1670913000000. Its totient is φ = 835378951680.

The previous prime is 1218317516797. The next prime is 1218317516821. The reversal of 1218317516815 is 5186157138121.

It is not a de Polignac number, because 1218317516815 - 2¹⁷ = 1218317385743 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32440 + ... + 1561309.

It is an arithmetic number, because the mean of its divisors is an integer number (104432062500).

Almost surely, 2^{1218317516815} is an apocalyptic number.

1218317516815 is a deficient number, since it is larger than the sum of its proper divisors (452595483185).

1218317516815 is a wasteful number, since it uses less digits than its factorization.

1218317516815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1615602.

The product of its digits is 403200, while the sum is 49.

The spelling of 1218317516815 in words is "one trillion, two hundred eighteen billion, three hundred seventeen million, five hundred sixteen thousand, eight hundred fifteen".