201212122221100 has 144 divisors (see below), whose sum is σ = 461649843768960. Its totient is φ = 76038816268800.

The previous prime is 201212122220969. The next prime is 201212122221107. The reversal of 201212122221100 is 1122221212102.

It is not an unprimeable number, because it can be changed into a prime (201212122221107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9999847 + ... + 22414753.

It is an arithmetic number, because the mean of its divisors is an integer number (3205901692840).

Almost surely, 2^{201212122221100} is an apocalyptic number.

201212122221100 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 201212122221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230824921884480).

201212122221100 is an abundant number, since it is smaller than the sum of its proper divisors (260437721547860).

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

201212122221100 is a wasteful number, since it uses less digits than its factorization.

201212122221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12415088 (or 12415081 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 201212122221100 its reverse (1122221212102), we get a palindrome (202334343433202).

The spelling of 201212122221100 in words is "two hundred one trillion, two hundred twelve billion, one hundred twenty-two million, two hundred twenty-one thousand, one hundred".