1221002002101 has 32 divisors (see below), whose sum is σ = 1874935123200. Its totient is φ = 692334429696.

The previous prime is 1221002002069. The next prime is 1221002002139. The reversal of 1221002002101 is 1012002001221.

It is not a de Polignac number, because 1221002002101 - 2⁵ = 1221002002069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221002102101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6924175 + ... + 7098323.

It is an arithmetic number, because the mean of its divisors is an integer number (58591722600).

Almost surely, 2^{1221002002101} is an apocalyptic number.

It is an amenable number.

1221002002101 is a deficient number, since it is larger than the sum of its proper divisors (653933121099).

1221002002101 is a wasteful number, since it uses less digits than its factorization.

1221002002101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176733.

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

Adding to 1221002002101 its reverse (1012002001221), we get a palindrome (2233004003322).

The spelling of 1221002002101 in words is "one trillion, two hundred twenty-one billion, two million, two thousand, one hundred one".