861560 has 64 divisors (see below), whose sum is σ = 2358720. Its totient is φ = 276480.

The previous prime is 861559. The next prime is 861563. The reversal of 861560 is 65168.

861560 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 an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 861560.

It is not an unprimeable number, because it can be changed into a prime (861563) 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, 4670 + ... + 4850.

It is an arithmetic number, because the mean of its divisors is an integer number (36855).

2⁸⁶¹⁵⁶⁰ 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 861560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1179360).

861560 is an abundant number, since it is smaller than the sum of its proper divisors (1497160).

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

861560 is a wasteful number, since it uses less digits than its factorization.

861560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216 (or 212 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 861560 is about 928.2025640990. The cubic root of 861560 is about 95.1543198213.

The spelling of 861560 in words is "eight hundred sixty-one thousand, five hundred sixty".