1221003110020 has 96 divisors (see below), whose sum is σ = 2836970438400. Its totient is φ = 439347769344.

The previous prime is 1221003109943. The next prime is 1221003110071. The reversal of 1221003110020 is 200113001221.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 687516 + ... + 1707244.

It is an arithmetic number, because the mean of its divisors is an integer number (29551775400).

Almost surely, 2^{1221003110020} is an apocalyptic number.

1221003110020 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 1221003110020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1418485219200).

1221003110020 is an abundant number, since it is smaller than the sum of its proper divisors (1615967328380).

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

1221003110020 is a wasteful number, since it uses less digits than its factorization.

1221003110020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019917 (or 1019915 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 1221003110020 its reverse (200113001221), we get a palindrome (1421116111241).

The spelling of 1221003110020 in words is "one trillion, two hundred twenty-one billion, three million, one hundred ten thousand, twenty".