2001001000 has 64 divisors (see below), whose sum is σ = 4699665360. Its totient is φ = 797440000.

The previous prime is 2001000977. The next prime is 2001001003. The reversal of 2001001000 is 1001002.

It can be written as a sum of positive squares in 8 ways, for example, as 4519876 + 1996481124 = 2126^2 + 44682^2 .

It is a Harshad number since it is a multiple of its sum of digits (4).

It is not an unprimeable number, because it can be changed into a prime (2001001003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 277440 + ... + 284560.

Almost surely, 2^2001001000 is an apocalyptic number.

2001001000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2001001000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2349832680).

2001001000 is an abundant number, since it is smaller than the sum of its proper divisors (2698664360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2001001000 is a wasteful number, since it uses less digits than its factorization.

2001001000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7423 (or 7409 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 4.

The square root of 2001001000 is about 44732.5496702345. The cubic root of 2001001000 is about 1260.1312116653.

Adding to 2001001000 its reverse (1001002), we get a palindrome (2002002002).

The spelling of 2001001000 in words is "two billion, one million, one thousand".