123861 has 16 divisors (see below), whose sum is σ = 181440. Its totient is φ = 74880.

The previous prime is 123853. The next prime is 123863. The reversal of 123861 is 168321.

It is not a de Polignac number, because 123861 - 2³ = 123853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2311 + ... + 2363.

It is an arithmetic number, because the mean of its divisors is an integer number (11340).

2¹²³⁸⁶¹ is an apocalyptic number.

It is an amenable number.

123861 is a deficient number, since it is larger than the sum of its proper divisors (57579).

123861 is a wasteful number, since it uses less digits than its factorization.

123861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116.

The product of its digits is 288, while the sum is 21.

The square root of 123861 is about 351.9389151543. The cubic root of 123861 is about 49.8476697143.

The spelling of 123861 in words is "one hundred twenty-three thousand, eight hundred sixty-one".