11858 has 18 divisors (see below), whose sum is σ = 22743. Its totient is φ = 4620.

The previous prime is 11839. The next prime is 11863. The reversal of 11858 is 85811.

11858 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 5929 + 5929 = 77^2 + 77^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=77.

It is a super-2 number, since 2×11858² = 281224328, which contains 22 as substring.

Its product of digits (320) is a multiple of the sum of its prime divisors (20).

It is a nialpdrome in base 13.

It is a zygodrome in base 13.

It is an unprimeable number.

11858 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1073 + ... + 1083.

2¹¹⁸⁵⁸ is an apocalyptic number.

11858 is a deficient number, since it is larger than the sum of its proper divisors (10885).

11858 is a wasteful number, since it uses less digits than its factorization.

11858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38 (or 20 counting only the distinct ones).

The product of its digits is 320, while the sum is 23.

The square root of 11858 is about 108.8944443027. The cubic root of 11858 is about 22.8036210520.

Adding to 11858 its sum of digits (23), we get a square (11881 = 109²).

The spelling of 11858 in words is "eleven thousand, eight hundred fifty-eight".