121221200100001 has 12 divisors (see below), whose sum is σ = 125014374202068. Its totient is φ = 117501067440224.

The previous prime is 121221200099959. The next prime is 121221200100023. The reversal of 121221200100001 is 100001002122121.

It can be written as a sum of positive squares in 2 ways, for example, as 102325869140625 + 18895330959376 = 10115625^2 + 4346876^2 .

It is not a de Polignac number, because 121221200100001 - 2¹³ = 121221200091809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121221200100031) 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 11 ways as a sum of consecutive naturals, for example, 165638110 + ... + 166368343.

It is an arithmetic number, because the mean of its divisors is an integer number (10417864516839).

Almost surely, 2^{121221200100001} is an apocalyptic number.

It is an amenable number.

121221200100001 is a deficient number, since it is larger than the sum of its proper divisors (3793174102067).

121221200100001 is an frugal number, since it uses more digits than its factorization.

121221200100001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332006672 (or 332006589 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 121221200100001 its reverse (100001002122121), we get a palindrome (221222202222122).

The spelling of 121221200100001 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, two hundred million, one hundred thousand, one".