851959 has 4 divisors (see below), whose sum is σ = 871816. Its totient is φ = 832104.

The previous prime is 851957. The next prime is 851971. The reversal of 851959 is 959158.

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

It is a cyclic number.

It is not a de Polignac number, because 851959 - 2¹ = 851957 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 (851953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9864 + ... + 9949.

It is an arithmetic number, because the mean of its divisors is an integer number (217954).

2⁸⁵¹⁹⁵⁹ is an apocalyptic number.

851959 is a deficient number, since it is larger than the sum of its proper divisors (19857).

851959 is a wasteful number, since it uses less digits than its factorization.

851959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19856.

The product of its digits is 16200, while the sum is 37.

The square root of 851959 is about 923.0162512112. The cubic root of 851959 is about 94.7995403729.

The spelling of 851959 in words is "eight hundred fifty-one thousand, nine hundred fifty-nine".