871640 has 64 divisors (see below), whose sum is σ = 2453760. Its totient is φ = 270720.

The previous prime is 871639. The next prime is 871643. The reversal of 871640 is 46178.

871640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (871643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2939 + ... + 3221.

It is an arithmetic number, because the mean of its divisors is an integer number (38340).

2⁸⁷¹⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 871640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1226880).

871640 is an abundant number, since it is smaller than the sum of its proper divisors (1582120).

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

871640 is a wasteful number, since it uses less digits than its factorization.

871640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312 (or 308 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 871640 is about 933.6166236738. The cubic root of 871640 is about 95.5239745004.

The spelling of 871640 in words is "eight hundred seventy-one thousand, six hundred forty".