1001221011000 has 384 divisors, whose sum is σ = 3870746904960. Its totient is φ = 228662784000.

The previous prime is 1001221010983. The next prime is 1001221011029. The reversal of 1001221011000 is 1101221001.

It is a happy number.

1001221011000 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 85737162 + ... + 85748838.

It is an arithmetic number, because the mean of its divisors is an integer number (10080070065).

Almost surely, 2^{1001221011000} is an apocalyptic number.

1001221011000 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 1001221011000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1935373452480).

1001221011000 is an abundant number, since it is smaller than the sum of its proper divisors (2869525893960).

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

1001221011000 is a wasteful number, since it uses less digits than its factorization.

1001221011000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13072 (or 13055 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 1001221011000 its reverse (1101221001), we get a palindrome (1002322232001).

The spelling of 1001221011000 in words is "one trillion, one billion, two hundred twenty-one million, eleven thousand".