861884156 has 96 divisors (see below), whose sum is σ = 1936650240. Its totient is φ = 326716416.

The previous prime is 861884119. The next prime is 861884183. The reversal of 861884156 is 651488168.

It is a self number, because there is not a number n which added to its sum of digits gives 861884156.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1419605 + ... + 1420211.

It is an arithmetic number, because the mean of its divisors is an integer number (20173440).

Almost surely, 2^861884156 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 861884156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (968325120).

861884156 is an abundant number, since it is smaller than the sum of its proper divisors (1074766084).

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

861884156 is a wasteful number, since it uses less digits than its factorization.

861884156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811 (or 809 counting only the distinct ones).

The product of its digits is 368640, while the sum is 47.

The square root of 861884156 is about 29357.8636143709. The cubic root of 861884156 is about 951.6625204352.

The spelling of 861884156 in words is "eight hundred sixty-one million, eight hundred eighty-four thousand, one hundred fifty-six".