123889 has 4 divisors (see below), whose sum is σ = 124660. Its totient is φ = 123120.

The previous prime is 123887. The next prime is 123911. The reversal of 123889 is 988321.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 87025 + 36864 = 295^2 + 192^2 .

It is a cyclic number.

It is not a de Polignac number, because 123889 - 2¹ = 123887 is a prime.

It is a Duffinian number.

123889 is a lucky number.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 123889.

It is not an unprimeable number, because it can be changed into a prime (123887) 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 3 ways as a sum of consecutive naturals, for example, 42 + ... + 499.

It is an arithmetic number, because the mean of its divisors is an integer number (31165).

2¹²³⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

123889 is a deficient number, since it is larger than the sum of its proper divisors (771).

123889 is an equidigital number, since it uses as much as digits as its factorization.

123889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 770.

The product of its digits is 3456, while the sum is 31.

The square root of 123889 is about 351.9786925369. The cubic root of 123889 is about 49.8514256170.

The spelling of 123889 in words is "one hundred twenty-three thousand, eight hundred eighty-nine".