818870217985 has 8 divisors (see below), whose sum is σ = 982749514536. Its totient is φ = 655026005760.

The previous prime is 818870217941. The next prime is 818870218007. The reversal of 818870217985 is 589712078818.

It can be written as a sum of positive squares in 4 ways, for example, as 140078781441 + 678791436544 = 374271^2 + 823888^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 818870217985 - 2²⁵ = 818836663553 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8719704 + ... + 8813113.

It is an arithmetic number, because the mean of its divisors is an integer number (122843689317).

Almost surely, 2^818870217985 is an apocalyptic number.

It is an amenable number.

818870217985 is a deficient number, since it is larger than the sum of its proper divisors (163879296551).

818870217985 is a wasteful number, since it uses less digits than its factorization.

818870217985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17542163.

The product of its (nonzero) digits is 18063360, while the sum is 64.

The spelling of 818870217985 in words is "eight hundred eighteen billion, eight hundred seventy million, two hundred seventeen thousand, nine hundred eighty-five".