1221211120101 has 64 divisors (see below), whose sum is σ = 2014780078080. Its totient is φ = 642384691200.

The previous prime is 1221211120037. The next prime is 1221211120117. The reversal of 1221211120101 is 1010211121221.

It is a happy number.

It is not a de Polignac number, because 1221211120101 - 2⁶ = 1221211120037 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221211120141) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3126901 + ... + 3495701.

It is an arithmetic number, because the mean of its divisors is an integer number (31480938720).

Almost surely, 2^{1221211120101} is an apocalyptic number.

It is an amenable number.

1221211120101 is a deficient number, since it is larger than the sum of its proper divisors (793568957979).

1221211120101 is a wasteful number, since it uses less digits than its factorization.

1221211120101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369066.

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

Adding to 1221211120101 its reverse (1010211121221), we get a palindrome (2231422241322).

The spelling of 1221211120101 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, one hundred twenty thousand, one hundred one".