111638 has 4 divisors (see below), whose sum is σ = 167460. Its totient is φ = 55818.

The previous prime is 111637. The next prime is 111641. The reversal of 111638 is 836111.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a nialpdrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27908 + ... + 27911.

It is an arithmetic number, because the mean of its divisors is an integer number (41865).

2¹¹¹⁶³⁸ is an apocalyptic number.

111638 is a deficient number, since it is larger than the sum of its proper divisors (55822).

111638 is an equidigital number, since it uses as much as digits as its factorization.

111638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55821.

The product of its digits is 144, while the sum is 20.

The square root of 111638 is about 334.1227319414. The cubic root of 111638 is about 48.1508564040.

Adding to 111638 its reverse (836111), we get a palindrome (947749).

The spelling of 111638 in words is "one hundred eleven thousand, six hundred thirty-eight".