1218550844165 has 16 divisors (see below), whose sum is σ = 1481451260400. Its totient is φ = 962130524160.

The previous prime is 1218550844113. The next prime is 1218550844207. The reversal of 1218550844165 is 5614480558121.

It can be written as a sum of positive squares in 8 ways, for example, as 100088078689 + 1118462765476 = 316367^2 + 1057574^2 .

It is not a de Polignac number, because 1218550844165 - 2⁶ = 1218550844101 is a prime.

It is a super-2 number, since 2×1218550844165² (a number of 25 digits) contains 22 as substring.

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, 5092076 + ... + 5326005.

It is an arithmetic number, because the mean of its divisors is an integer number (92590703775).

Almost surely, 2^{1218550844165} is an apocalyptic number.

It is an amenable number.

1218550844165 is a deficient number, since it is larger than the sum of its proper divisors (262900416235).

1218550844165 is a wasteful number, since it uses less digits than its factorization.

1218550844165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10418392.

The product of its (nonzero) digits is 1536000, while the sum is 50.

The spelling of 1218550844165 in words is "one trillion, two hundred eighteen billion, five hundred fifty million, eight hundred forty-four thousand, one hundred sixty-five".