1211121120221 has 32 divisors (see below), whose sum is σ = 1309516053120. Its totient is φ = 1117907481600.

The previous prime is 1211121120191. The next prime is 1211121120269. The reversal of 1211121120221 is 1220211211121.

It is a cyclic number.

It is not a de Polignac number, because 1211121120221 - 2²⁶ = 1211054011357 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211121120221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211121126221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11874281 + ... + 11975841.

It is an arithmetic number, because the mean of its divisors is an integer number (40922376660).

Almost surely, 2^{1211121120221} is an apocalyptic number.

It is an amenable number.

1211121120221 is a deficient number, since it is larger than the sum of its proper divisors (98394932899).

1211121120221 is a wasteful number, since it uses less digits than its factorization.

1211121120221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101837.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1211121120221 its reverse (1220211211121), we get a palindrome (2431332331342).

The spelling of 1211121120221 in words is "one trillion, two hundred eleven billion, one hundred twenty-one million, one hundred twenty thousand, two hundred twenty-one".