1803 has 4 divisors (see below), whose sum is σ = 2408. Its totient is φ = 1200.

The previous prime is 1801. The next prime is 1811. The reversal of 1803 is 3081.

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

It is not a de Polignac number, because 1803 - 2¹ = 1801 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (1801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 298 + ... + 303.

It is an arithmetic number, because the mean of its divisors is an integer number (602).

2¹⁸⁰³ is an apocalyptic number.

1803 is a deficient number, since it is larger than the sum of its proper divisors (605).

1803 is an equidigital number, since it uses as much as digits as its factorization.

1803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1803 is about 42.4617474911. The cubic root of 1803 is about 12.1711582424.

Adding to 1803 its reverse (3081), we get a palindrome (4884).

The spelling of 1803 in words is "one thousand, eight hundred three".