2001203121 has 4 divisors (see below), whose sum is σ = 2668270832. Its totient is φ = 1334135412.

The previous prime is 2001203119. The next prime is 2001203143. The reversal of 2001203121 is 1213021002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2001203121 - 2¹ = 2001203119 is a prime.

It is a super-3 number, since 3×2001203121³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001203097 and 2001203106.

It is not an unprimeable number, because it can be changed into a prime (2001203221) 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, 333533851 + ... + 333533856.

It is an arithmetic number, because the mean of its divisors is an integer number (667067708).

Almost surely, 2^2001203121 is an apocalyptic number.

It is an amenable number.

2001203121 is a deficient number, since it is larger than the sum of its proper divisors (667067711).

2001203121 is an equidigital number, since it uses as much as digits as its factorization.

2001203121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 667067710.

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

The square root of 2001203121 is about 44734.8088293669. The cubic root of 2001203121 is about 1260.1736388314.

Adding to 2001203121 its reverse (1213021002), we get a palindrome (3214224123).

The spelling of 2001203121 in words is "two billion, one million, two hundred three thousand, one hundred twenty-one".