1221010220001 has 64 divisors (see below), whose sum is σ = 1930349998080. Its totient is φ = 676759587840.

The previous prime is 1221010219921. The next prime is 1221010220063. The reversal of 1221010220001 is 1000220101221.

It is not a de Polignac number, because 1221010220001 - 2¹⁰ = 1221010218977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221010220071) 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 63 ways as a sum of consecutive naturals, for example, 189978150 + ... + 189984576.

It is an arithmetic number, because the mean of its divisors is an integer number (30161718720).

Almost surely, 2^{1221010220001} is an apocalyptic number.

1221010220001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221010220001 is a deficient number, since it is larger than the sum of its proper divisors (709339778079).

1221010220001 is a wasteful number, since it uses less digits than its factorization.

1221010220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10486.

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

Adding to 1221010220001 its reverse (1000220101221), we get a palindrome (2221230321222).

The spelling of 1221010220001 in words is "one trillion, two hundred twenty-one billion, ten million, two hundred twenty thousand, one".