2001021013 has 4 divisors (see below), whose sum is σ = 2055102700. Its totient is φ = 1946939328.

The previous prime is 2001020981. The next prime is 2001021053. The reversal of 2001021013 is 3101201002.

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

It can be written as a sum of positive squares in 2 ways, for example, as 772728804 + 1228292209 = 27798^2 + 35047^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001021013 - 2⁵ = 2001020981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001021053) 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, 27040788 + ... + 27040861.

It is an arithmetic number, because the mean of its divisors is an integer number (513775675).

Almost surely, 2^2001021013 is an apocalyptic number.

It is an amenable number.

2001021013 is a deficient number, since it is larger than the sum of its proper divisors (54081687).

2001021013 is an equidigital number, since it uses as much as digits as its factorization.

2001021013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54081686.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 2001021013 is about 44732.7733658444. The cubic root of 2001021013 is about 1260.1354127163.

Adding to 2001021013 its reverse (3101201002), we get a palindrome (5102222015).

The spelling of 2001021013 in words is "two billion, one million, twenty-one thousand, thirteen".