861105 has 32 divisors (see below), whose sum is σ = 1612800. Its totient is φ = 384192.

The previous prime is 861089. The next prime is 861109. The reversal of 861105 is 501168.

861105 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 861105 - 2⁴ = 861089 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an Ulam number.

It is a Curzon number.

861105 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861109) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6126 + ... + 6264.

It is an arithmetic number, because the mean of its divisors is an integer number (50400).

2⁸⁶¹¹⁰⁵ is an apocalyptic number.

It is an amenable number.

861105 is a deficient number, since it is larger than the sum of its proper divisors (751695).

861105 is a wasteful number, since it uses less digits than its factorization.

861105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 861105 is about 927.9574343686. The cubic root of 861105 is about 95.1375661654.

The spelling of 861105 in words is "eight hundred sixty-one thousand, one hundred five".