847778616317 has 4 divisors (see below), whose sum is σ = 847842310140. Its totient is φ = 847714922496.

The previous prime is 847778616259. The next prime is 847778616337. The reversal of 847778616317 is 713616877748.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 198925812121 + 648852804196 = 446011^2 + 805514^2 .

It is a cyclic number.

It is not a de Polignac number, because 847778616317 - 2³⁴ = 830598747133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (847778616337) 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, 31826942 + ... + 31853567.

It is an arithmetic number, because the mean of its divisors is an integer number (211960577535).

Almost surely, 2^847778616317 is an apocalyptic number.

It is an amenable number.

847778616317 is a deficient number, since it is larger than the sum of its proper divisors (63693823).

847778616317 is a wasteful number, since it uses less digits than its factorization.

847778616317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63693822.

The product of its digits is 66382848, while the sum is 65.

The spelling of 847778616317 in words is "eight hundred forty-seven billion, seven hundred seventy-eight million, six hundred sixteen thousand, three hundred seventeen".