16538 has 4 divisors (see below), whose sum is σ = 24810. Its totient is φ = 8268.

The previous prime is 16529. The next prime is 16547. The reversal of 16538 is 83561.

16538 is an esthetic number in base 5, because in such base its adjacent digits differ by 1.

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

It is an interprime number because it is at equal distance from previous prime (16529) and next prime (16547).

It can be written as a sum of positive squares in only one way, i.e., 10609 + 5929 = 103^2 + 77^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4133 + ... + 4136.

2¹⁶⁵³⁸ is an apocalyptic number.

16538 is a deficient number, since it is larger than the sum of its proper divisors (8272).

16538 is an equidigital number, since it uses as much as digits as its factorization.

16538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8271.

The product of its digits is 720, while the sum is 23.

The square root of 16538 is about 128.6001555209. The cubic root of 16538 is about 25.4777455459.

Adding to 16538 its sum of digits (23), we get a palindrome (16561).

It can be divided in two parts, 1653 and 8, that added together give a palindrome (1661).

The spelling of 16538 in words is "sixteen thousand, five hundred thirty-eight".