871851 has 4 divisors (see below), whose sum is σ = 1162472. Its totient is φ = 581232.

The previous prime is 871837. The next prime is 871867. The reversal of 871851 is 158178.

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

It is not a de Polignac number, because 871851 - 2¹⁴ = 855467 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (875851) 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, 145306 + ... + 145311.

It is an arithmetic number, because the mean of its divisors is an integer number (290618).

2⁸⁷¹⁸⁵¹ is an apocalyptic number.

871851 is a deficient number, since it is larger than the sum of its proper divisors (290621).

871851 is a wasteful number, since it uses less digits than its factorization.

871851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290620.

The product of its digits is 2240, while the sum is 30.

The square root of 871851 is about 933.7296182515. The cubic root of 871851 is about 95.5316817850.

The spelling of 871851 in words is "eight hundred seventy-one thousand, eight hundred fifty-one".