2001021440 has 80 divisors (see below), whose sum is σ = 5233995360. Its totient is φ = 727633920.

The previous prime is 2001021433. The next prime is 2001021481. The reversal of 2001021440 is 441201002.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7370 + ... + 63689.

It is an arithmetic number, because the mean of its divisors is an integer number (65424942).

Almost surely, 2^2001021440 is an apocalyptic number.

2001021440 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 2001021440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2616997680).

2001021440 is an abundant number, since it is smaller than the sum of its proper divisors (3232973920).

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

2001021440 is an equidigital number, since it uses as much as digits as its factorization.

2001021440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71093 (or 71077 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 2001021440 is about 44732.7781386312. The cubic root of 2001021440 is about 1260.1355023502.

Adding to 2001021440 its reverse (441201002), we get a palindrome (2442222442).

The spelling of 2001021440 in words is "two billion, one million, twenty-one thousand, four hundred forty".