105861 has 12 divisors (see below), whose sum is σ = 163616. Its totient is φ = 59640.

The previous prime is 105829. The next prime is 105863. The reversal of 105861 is 168501.

It is not a de Polignac number, because 105861 - 2⁵ = 105829 is a prime.

It is a super-2 number, since 2×105861² = 22413102642, which contains 22 as substring.

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

It is a Duffinian number.

It is a Curzon number.

105861 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (105863) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1456 + ... + 1526.

2¹⁰⁵⁸⁶¹ is an apocalyptic number.

It is an amenable number.

105861 is a deficient number, since it is larger than the sum of its proper divisors (57755).

105861 is an frugal number, since it uses more digits than its factorization.

105861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 81 counting only the distinct ones).

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

The square root of 105861 is about 325.3628743419. The cubic root of 105861 is about 47.3055392381.

Multiplying 105861 by its sum of digits (21), we get a square (2223081 = 1491²).

105861 divided by its sum of digits (21) gives a square (5041 = 71²).

The spelling of 105861 in words is "one hundred five thousand, eight hundred sixty-one".