1221101012121 has 32 divisors (see below), whose sum is σ = 1661569459200. Its totient is φ = 797535046464.

The previous prime is 1221101012107. The next prime is 1221101012221. The reversal of 1221101012121 is 1212101011221.

It is a happy number.

It is not a de Polignac number, because 1221101012121 - 2²² = 1221096817817 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221101012121.

It is not an unprimeable number, because it can be changed into a prime (1221101012101) 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 31 ways as a sum of consecutive naturals, for example, 19632730 + ... + 19694828.

It is an arithmetic number, because the mean of its divisors is an integer number (51924045600).

Almost surely, 2^{1221101012121} is an apocalyptic number.

It is an amenable number.

1221101012121 is a deficient number, since it is larger than the sum of its proper divisors (440468447079).

1221101012121 is a wasteful number, since it uses less digits than its factorization.

1221101012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62845.

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

Adding to 1221101012121 its reverse (1212101011221), we get a palindrome (2433202023342).

The spelling of 1221101012121 in words is "one trillion, two hundred twenty-one billion, one hundred one million, twelve thousand, one hundred twenty-one".