917878348817 has 12 divisors (see below), whose sum is σ = 944240317020. Its totient is φ = 892233976896.

The previous prime is 917878348787. The next prime is 917878348819. The reversal of 917878348817 is 718843878719.

It can be written as a sum of positive squares in 6 ways, for example, as 22733402176 + 895144946641 = 150776^2 + 946121^2 .

It is a de Polignac number, because none of the positive numbers 2^k-917878348817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (917878348819) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1149863 + ... + 1777059.

It is an arithmetic number, because the mean of its divisors is an integer number (78686693085).

Almost surely, 2^917878348817 is an apocalyptic number.

It is an amenable number.

917878348817 is a deficient number, since it is larger than the sum of its proper divisors (26361968203).

917878348817 is a wasteful number, since it uses less digits than its factorization.

917878348817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 628340 (or 628303 counting only the distinct ones).

The product of its digits is 151732224, while the sum is 71.

The spelling of 917878348817 in words is "nine hundred seventeen billion, eight hundred seventy-eight million, three hundred forty-eight thousand, eight hundred seventeen".