840217085 has 4 divisors (see below), whose sum is σ = 1008260508. Its totient is φ = 672173664.

The previous prime is 840217067. The next prime is 840217093. The reversal of 840217085 is 580712048.

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 128074489 + 712142596 = 11317^2 + 26686^2 .

It is a cyclic number.

It is not a de Polignac number, because 840217085 - 2¹⁰ = 840216061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 84021704 + ... + 84021713.

It is an arithmetic number, because the mean of its divisors is an integer number (252065127).

Almost surely, 2^840217085 is an apocalyptic number.

It is an amenable number.

840217085 is a deficient number, since it is larger than the sum of its proper divisors (168043423).

840217085 is a wasteful number, since it uses less digits than its factorization.

840217085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168043422.

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 840217085 is about 28986.4983224949. The cubic root of 840217085 is about 943.6200700622.

The spelling of 840217085 in words is "eight hundred forty million, two hundred seventeen thousand, eighty-five".