11138 has 4 divisors (see below), whose sum is σ = 16710. Its totient is φ = 5568.

The previous prime is 11131. The next prime is 11149. The reversal of 11138 is 83111.

Added to its reverse (83111) it gives a square (94249 = 307²).

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

It can be written as a sum of positive squares in only one way, i.e., 10609 + 529 = 103^2 + 23^2 .

It is a Curzon number.

It is a plaindrome in base 10 and base 15.

It is a nialpdrome in base 7 and base 12.

It is not an unprimeable number, because it can be changed into a prime (11131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2783 + ... + 2786.

2¹¹¹³⁸ is an apocalyptic number.

11138 is a deficient number, since it is larger than the sum of its proper divisors (5572).

11138 is an equidigital number, since it uses as much as digits as its factorization.

11138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5571.

The product of its digits is 24, while the sum is 14.

The square root of 11138 is about 105.5367234663. The cubic root of 11138 is about 22.3324174769.

Adding to 11138 its reverse (83111), we get a palindrome (94249).

The spelling of 11138 in words is "eleven thousand, one hundred thirty-eight".