1001001221220 has 384 divisors, whose sum is σ = 3864921403392. Its totient is φ = 186810624000.

The previous prime is 1001001221189. The next prime is 1001001221273. The reversal of 1001001221220 is 221221001001.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 1001001221196 and 1001001221205.

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 127 ways as a sum of consecutive naturals, for example, 1996995 + ... + 2447445.

It is an arithmetic number, because the mean of its divisors is an integer number (10064899488).

Almost surely, 2^{1001001221220} is an apocalyptic number.

1001001221220 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 1001001221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1932460701696).

1001001221220 is an abundant number, since it is smaller than the sum of its proper divisors (2863920182172).

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

1001001221220 is a wasteful number, since it uses less digits than its factorization.

1001001221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450531 (or 450529 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 1001001221220 its reverse (221221001001), we get a palindrome (1222222222221).

It can be divided in two parts, 1001001 and 221220, that added together give a palindrome (1222221).

The spelling of 1001001221220 in words is "one trillion, one billion, one million, two hundred twenty-one thousand, two hundred twenty".