851941985 has 4 divisors (see below), whose sum is σ = 1022330388. Its totient is φ = 681553584.

The previous prime is 851941973. The next prime is 851941991. The reversal of 851941985 is 589149158.

851941985 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 498539584 + 353402401 = 22328^2 + 18799^2 .

It is a cyclic number.

It is not a de Polignac number, because 851941985 - 2¹⁰ = 851940961 is a prime.

It is a Duffinian number.

It is a Curzon 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, 85194194 + ... + 85194203.

It is an arithmetic number, because the mean of its divisors is an integer number (255582597).

Almost surely, 2^851941985 is an apocalyptic number.

It is an amenable number.

851941985 is a deficient number, since it is larger than the sum of its proper divisors (170388403).

851941985 is a wasteful number, since it uses less digits than its factorization.

851941985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170388402.

The product of its digits is 518400, while the sum is 50.

The square root of 851941985 is about 29188.0452411599. The cubic root of 851941985 is about 947.9890926867.

The spelling of 851941985 in words is "eight hundred fifty-one million, nine hundred forty-one thousand, nine hundred eighty-five".