201100001221 has 16 divisors (see below), whose sum is σ = 232153671168. Its totient is φ = 170628336000.

The previous prime is 201100001183. The next prime is 201100001251. The reversal of 201100001221 is 122100001102.

It is a cyclic number.

It is not a de Polignac number, because 201100001221 - 2³³ = 192510066629 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201100001198 and 201100001207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201100001251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3587076 + ... + 3642706.

It is an arithmetic number, because the mean of its divisors is an integer number (14509604448).

Almost surely, 2^201100001221 is an apocalyptic number.

It is an amenable number.

201100001221 is a deficient number, since it is larger than the sum of its proper divisors (31053669947).

201100001221 is a wasteful number, since it uses less digits than its factorization.

201100001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60852.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 201100001221 its reverse (122100001102), we get a palindrome (323200002323).

The spelling of 201100001221 in words is "two hundred one billion, one hundred million, one thousand, two hundred twenty-one".