850666803857 has 4 divisors (see below), whose sum is σ = 916102711860. Its totient is φ = 785230895856.

The previous prime is 850666803851. The next prime is 850666803923. The reversal of 850666803857 is 758308666058.

It is a Cunningham number, because it is equal to 922316²+1.

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 125837629696 + 724829174161 = 354736^2 + 851369^2 .

It is a cyclic number.

It is not a de Polignac number, because 850666803857 - 2¹² = 850666799761 is a prime.

It is a super-2 number, since 2×850666803857² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 850666803857.

It is not an unprimeable number, because it can be changed into a prime (850666803851) 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, 32717953982 + ... + 32717954007.

It is an arithmetic number, because the mean of its divisors is an integer number (229025677965).

Almost surely, 2^850666803857 is an apocalyptic number.

It is an amenable number.

850666803857 is a deficient number, since it is larger than the sum of its proper divisors (65435908003).

850666803857 is a wasteful number, since it uses less digits than its factorization.

850666803857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65435908002.

The product of its (nonzero) digits is 58060800, while the sum is 62.

The spelling of 850666803857 in words is "eight hundred fifty billion, six hundred sixty-six million, eight hundred three thousand, eight hundred fifty-seven".