861785560 has 64 divisors (see below), whose sum is σ = 1999559520. Its totient is φ = 334064640.

The previous prime is 861785549. The next prime is 861785569. The reversal of 861785560 is 65587168.

861785560 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 861785560.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861785569) 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, 255807 + ... + 259153.

Almost surely, 2^861785560 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 861785560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (999779760).

861785560 is an abundant number, since it is smaller than the sum of its proper divisors (1137773960).

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

861785560 is a wasteful number, since it uses less digits than its factorization.

861785560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3556 (or 3552 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 46.

The square root of 861785560 is about 29356.1843569630. The cubic root of 861785560 is about 951.6262302929.

The spelling of 861785560 in words is "eight hundred sixty-one million, seven hundred eighty-five thousand, five hundred sixty".