118381 has 4 divisors (see below), whose sum is σ = 123552. Its totient is φ = 113212.

The previous prime is 118373. The next prime is 118387. The reversal of 118381 is 183811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 183811 = 397 ⋅463.

It is a cyclic number.

It is not a de Polignac number, because 118381 - 2³ = 118373 is a prime.

It is a super-2 number, since 2×118381² = 28028122322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (118387) 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, 2551 + ... + 2596.

It is an arithmetic number, because the mean of its divisors is an integer number (30888).

2¹¹⁸³⁸¹ is an apocalyptic number.

It is an amenable number.

118381 is a deficient number, since it is larger than the sum of its proper divisors (5171).

118381 is an equidigital number, since it uses as much as digits as its factorization.

118381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5170.

The product of its digits is 192, while the sum is 22.

The square root of 118381 is about 344.0654007598. The cubic root of 118381 is about 49.1014142834.

The spelling of 118381 in words is "one hundred eighteen thousand, three hundred eighty-one".