16138 has 4 divisors (see below), whose sum is σ = 24210. Its totient is φ = 8068.

The previous prime is 16127. The next prime is 16139. The reversal of 16138 is 83161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83161 = 13 ⋅6397.

It can be written as a sum of positive squares in only one way, i.e., 16129 + 9 = 127^2 + 3^2 .

It is a zygodrome in base 4.

It is not an unprimeable number, because it can be changed into a prime (16139) by changing a digit.

16138 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4033 + ... + 4036.

2¹⁶¹³⁸ is an apocalyptic number.

16138 is a deficient number, since it is larger than the sum of its proper divisors (8072).

16138 is an equidigital number, since it uses as much as digits as its factorization.

16138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8071.

The product of its digits is 144, while the sum is 19.

The square root of 16138 is about 127.0354281293. The cubic root of 16138 is about 25.2706591699.

Adding to 16138 its reverse (83161), we get a palindrome (99299).

The spelling of 16138 in words is "sixteen thousand, one hundred thirty-eight".