20001222120100 has 72 divisors (see below), whose sum is σ = 46756788624000. Its totient is φ = 7382622218880.

The previous prime is 20001222120059. The next prime is 20001222120211. The reversal of 20001222120100 is 102122210002.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1385151 + ... + 6474649.

It is an arithmetic number, because the mean of its divisors is an integer number (649399842000).

Almost surely, 2^{20001222120100} is an apocalyptic number.

20001222120100 is a gapful number since it is divisible by the number (20) 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 20001222120100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23378394312000).

20001222120100 is an abundant number, since it is smaller than the sum of its proper divisors (26755566503900).

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

20001222120100 is a wasteful number, since it uses less digits than its factorization.

20001222120100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5092549 (or 5092542 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20001222120100 its reverse (102122210002), we get a palindrome (20103344330102).

The spelling of 20001222120100 in words is "twenty trillion, one billion, two hundred twenty-two million, one hundred twenty thousand, one hundred".