2001321322440 has 192 divisors, whose sum is σ = 6612862697280. Its totient is φ = 484178956800.

The previous prime is 2001321322411. The next prime is 2001321322519. The reversal of 2001321322440 is 442231231002.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 2001321322440.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6988962 + ... + 7269678.

It is an arithmetic number, because the mean of its divisors is an integer number (34441993215).

Almost surely, 2^{2001321322440} is an apocalyptic number.

2001321322440 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 2001321322440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3306431348640).

2001321322440 is an abundant number, since it is smaller than the sum of its proper divisors (4611541374840).

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

2001321322440 is a wasteful number, since it uses less digits than its factorization.

2001321322440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281244 (or 281229 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 2001321322440 its reverse (442231231002), we get a palindrome (2443552553442).

The spelling of 2001321322440 in words is "two trillion, one billion, three hundred twenty-one million, three hundred twenty-two thousand, four hundred forty".