1001201221020 has 864 divisors, whose sum is σ = 3957133533696. Its totient is φ = 186810624000.

The previous prime is 1001201220997. The next prime is 1001201221049. The reversal of 1001201221020 is 201221021001.

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 = 1001201220987 and 1001201221005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 202219545 + ... + 202224495.

It is an arithmetic number, because the mean of its divisors is an integer number (4580015664).

Almost surely, 2^{1001201221020} is an apocalyptic number.

1001201221020 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 1001201221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1978566766848).

1001201221020 is an abundant number, since it is smaller than the sum of its proper divisors (2955932312676).

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

1001201221020 is a wasteful number, since it uses less digits than its factorization.

1001201221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5051 (or 5029 counting only the distinct ones).

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

Adding to 1001201221020 its reverse (201221021001), we get a palindrome (1202422242021).

It can be divided in two parts, 1001201 and 221020, that added together give a palindrome (1222221).

The spelling of 1001201221020 in words is "one trillion, one billion, two hundred one million, two hundred twenty-one thousand, twenty".