871840 has 24 divisors (see below), whose sum is σ = 2060100. Its totient is φ = 348672.

The previous prime is 871837. The next prime is 871867. The reversal of 871840 is 48178.

It can be written as a sum of positive squares in 2 ways, for example, as 795664 + 76176 = 892^2 + 276^2 .

It is a junction number, because it is equal to n+sod(n) for n = 871799 and 871808.

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, 2565 + ... + 2884.

2⁸⁷¹⁸⁴⁰ is an apocalyptic number.

871840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

871840 is an abundant number, since it is smaller than the sum of its proper divisors (1188260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

871840 is a wasteful number, since it uses less digits than its factorization.

871840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5464 (or 5456 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 871840 is about 933.7237278767. The cubic root of 871840 is about 95.5312800141.

It can be divided in two parts, 871 and 840, that added together give a triangular number (1711 = T₅₈).

The spelling of 871840 in words is "eight hundred seventy-one thousand, eight hundred forty".