861805224 has 128 divisors (see below), whose sum is σ = 2743372800. Its totient is φ = 245557440.

The previous prime is 861805201. The next prime is 861805279. The reversal of 861805224 is 422508168.

861805224 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×861805224² = 1485416488227380352, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 887059 + ... + 888029.

It is an arithmetic number, because the mean of its divisors is an integer number (21432600).

Almost surely, 2^861805224 is an apocalyptic number.

861805224 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861805224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1371686400).

861805224 is an abundant number, since it is smaller than the sum of its proper divisors (1881567576).

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

861805224 is a wasteful number, since it uses less digits than its factorization.

861805224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1580 (or 1570 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 861805224 is about 29356.5192759632. The cubic root of 861805224 is about 951.6334682249.

The spelling of 861805224 in words is "eight hundred sixty-one million, eight hundred five thousand, two hundred twenty-four".