12861 has 6 divisors (see below), whose sum is σ = 18590. Its totient is φ = 8568.

The previous prime is 12853. The next prime is 12889. The reversal of 12861 is 16821.

It can be written as a sum of positive squares in only one way, i.e., 8100 + 4761 = 90^2 + 69^2 .

It is not a de Polignac number, because 12861 - 2³ = 12853 is a prime.

It is a Duffinian number.

12861 is a lucky number.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 706 + ... + 723.

2¹²⁸⁶¹ is an apocalyptic number.

It is an amenable number.

12861 is a deficient number, since it is larger than the sum of its proper divisors (5729).

12861 is a wasteful number, since it uses less digits than its factorization.

12861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1435 (or 1432 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 12861 is about 113.4063490286. The cubic root of 12861 is about 23.4292424243.

The spelling of 12861 in words is "twelve thousand, eight hundred sixty-one".