2001321003 has 24 divisors (see below), whose sum is σ = 2961597184. Its totient is φ = 1201123440.

The previous prime is 2001320989. The next prime is 2001321019. The reversal of 2001321003 is 3001231002.

It is a happy number.

It is not a de Polignac number, because 2001321003 - 2⁸ = 2001320747 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2001321003.

It is not an unprimeable number, because it can be changed into a prime (2001321043) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10626 + ... + 64152.

Almost surely, 2^2001321003 is an apocalyptic number.

2001321003 is a deficient number, since it is larger than the sum of its proper divisors (960276181).

2001321003 is a wasteful number, since it uses less digits than its factorization.

2001321003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53655 (or 53644 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 2001321003 is about 44736.1263745533. The cubic root of 2001321003 is about 1260.1983820922.

Adding to 2001321003 its reverse (3001231002), we get a palindrome (5002552005).

Subtracting 2001321003 from its reverse (3001231002), we obtain a palindrome (999909999).

The spelling of 2001321003 in words is "two billion, one million, three hundred twenty-one thousand, three".