861844 has 6 divisors (see below), whose sum is σ = 1508234. Its totient is φ = 430920.

The previous prime is 861829. The next prime is 861853. The reversal of 861844 is 448168.

It can be written as a sum of positive squares in only one way, i.e., 659344 + 202500 = 812^2 + 450^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107727 + ... + 107734.

2⁸⁶¹⁸⁴⁴ is an apocalyptic number.

It is an amenable number.

861844 is a deficient number, since it is larger than the sum of its proper divisors (646390).

861844 is a wasteful number, since it uses less digits than its factorization.

861844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215465 (or 215463 counting only the distinct ones).

The product of its digits is 6144, while the sum is 31.

The square root of 861844 is about 928.3555353419. The cubic root of 861844 is about 95.1647740586.

The spelling of 861844 in words is "eight hundred sixty-one thousand, eight hundred forty-four".