201221100010100 has 72 divisors (see below), whose sum is σ = 455675311246848. Its totient is φ = 76982056905600.

The previous prime is 201221100009997. The next prime is 201221100010109. The reversal of 201221100010100 is 1010001122102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201221100010109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21846365 + ... + 29659835.

Almost surely, 2^{201221100010100} is an apocalyptic number.

201221100010100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201221100010100 is an abundant number, since it is smaller than the sum of its proper divisors (254454211236748).

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

201221100010100 is a wasteful number, since it uses less digits than its factorization.

201221100010100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7824705 (or 7824698 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 201221100010100 its reverse (1010001122102), we get a palindrome (202231101132202).

The spelling of 201221100010100 in words is "two hundred one trillion, two hundred twenty-one billion, one hundred million, ten thousand, one hundred".