221200100121 has 48 divisors (see below), whose sum is σ = 398994603392. Its totient is φ = 106069962240.

The previous prime is 221200100117. The next prime is 221200100141. The reversal of 221200100121 is 121001002122.

It is not a de Polignac number, because 221200100121 - 2² = 221200100117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221200100097 and 221200100106.

It is not an unprimeable number, because it can be changed into a prime (221200100141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3315136 + ... + 3381201.

Almost surely, 2^221200100121 is an apocalyptic number.

221200100121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221200100121 is a deficient number, since it is larger than the sum of its proper divisors (177794503271).

221200100121 is a wasteful number, since it uses less digits than its factorization.

221200100121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6696382 (or 6696371 counting only the distinct ones).

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

Adding to 221200100121 its reverse (121001002122), we get a palindrome (342201102243).

The spelling of 221200100121 in words is "two hundred twenty-one billion, two hundred million, one hundred thousand, one hundred twenty-one".