16003 has 4 divisors (see below), whose sum is σ = 17248. Its totient is φ = 14760.

The previous prime is 16001. The next prime is 16007. The reversal of 16003 is 30061.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30061 = 23 ⋅1307.

It is a cyclic number.

It is not a de Polignac number, because 16003 - 2¹ = 16001 is a prime.

It is an Ulam number.

It is the 127-th Hogben number.

It is a Duffinian number.

16003 is a lucky number.

It is a nialpdrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (16001) by changing a digit.

It is a nontrivial repunit in base 126.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 603 + ... + 628.

It is an arithmetic number, because the mean of its divisors is an integer number (4312).

2¹⁶⁰⁰³ is an apocalyptic number.

16003 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

16003 is a deficient number, since it is larger than the sum of its proper divisors (1245).

16003 is a wasteful number, since it uses less digits than its factorization.

16003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1244.

The product of its (nonzero) digits is 18, while the sum is 10.

The square root of 16003 is about 126.5029643921. The cubic root of 16003 is about 25.1999958008.

Adding to 16003 its reverse (30061), we get a palindrome (46064).

The spelling of 16003 in words is "sixteen thousand, three".