1221211212201 has 48 divisors (see below), whose sum is σ = 1838443875840. Its totient is φ = 780282720000.

The previous prime is 1221211212187. The next prime is 1221211212211. The reversal of 1221211212201 is 1022121121221.

1221211212201 is a `hidden beast` number, since 1 + 221 + 211 + 212 + 20 + 1 = 666.

It is not a de Polignac number, because 1221211212201 - 2²⁵ = 1221177657769 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221211212211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 74225026 + ... + 74241476.

It is an arithmetic number, because the mean of its divisors is an integer number (38300914080).

Almost surely, 2^{1221211212201} is an apocalyptic number.

It is an amenable number.

1221211212201 is a deficient number, since it is larger than the sum of its proper divisors (617232663639).

1221211212201 is a wasteful number, since it uses less digits than its factorization.

1221211212201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19038 (or 19035 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1221211212201 its reverse (1022121121221), we get a palindrome (2243332333422).

It can be divided in two parts, 122121121220 and 1, that added together give a palindrome (122121121221).

The spelling of 1221211212201 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, two hundred twelve thousand, two hundred one".