1001221002000 has 240 divisors, whose sum is σ = 3532988218032. Its totient is φ = 264239308800.

The previous prime is 1001221001993. The next prime is 1001221002121. The reversal of 1001221002000 is 2001221001.

It can be written as a sum of positive squares in 8 ways, for example, as 316689813504 + 684531188496 = 562752^2 + 827364^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1459282 + ... + 2032718.

Almost surely, 2^{1001221002000} is an apocalyptic number.

1001221002000 is a gapful number since it is divisible by the number (10) 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 1001221002000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1766494109016).

1001221002000 is an abundant number, since it is smaller than the sum of its proper divisors (2531767216032).

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

1001221002000 is a wasteful number, since it uses less digits than its factorization.

1001221002000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573563 (or 573544 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 1001221002000 its reverse (2001221001), we get a palindrome (1003222223001).

The spelling of 1001221002000 in words is "one trillion, one billion, two hundred twenty-one million, two thousand".