1211221102101 has 16 divisors (see below), whose sum is σ = 1679609194560. Its totient is φ = 775772565120.

The previous prime is 1211221102079. The next prime is 1211221102103. The reversal of 1211221102101 is 1012011221121.

It is a happy number.

It is not a de Polignac number, because 1211221102101 - 2⁶ = 1211221102037 is a prime.

It is a super-2 number, since 2×1211221102101² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211221102103) 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 15 ways as a sum of consecutive naturals, for example, 76953696 + ... + 76969433.

It is an arithmetic number, because the mean of its divisors is an integer number (104975574660).

Almost surely, 2^{1211221102101} is an apocalyptic number.

It is an amenable number.

1211221102101 is a deficient number, since it is larger than the sum of its proper divisors (468388092459).

1211221102101 is a wasteful number, since it uses less digits than its factorization.

1211221102101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153923236.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1211221102101 its reverse (1012011221121), we get a palindrome (2223232323222).

The spelling of 1211221102101 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred two thousand, one hundred one".