1211100221211 has 64 divisors (see below), whose sum is σ = 1833011970048. Its totient is φ = 707136117248.

The previous prime is 1211100221167. The next prime is 1211100221333. The reversal of 1211100221211 is 1121220011121.

It is a happy number.

It is not a de Polignac number, because 1211100221211 - 2⁶ = 1211100221147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211100201211) 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, 9141106 + ... + 9272648.

It is an arithmetic number, because the mean of its divisors is an integer number (28640812032).

Almost surely, 2^{1211100221211} is an apocalyptic number.

1211100221211 is a deficient number, since it is larger than the sum of its proper divisors (621911748837).

1211100221211 is a wasteful number, since it uses less digits than its factorization.

1211100221211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131800.

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

Adding to 1211100221211 its reverse (1121220011121), we get a palindrome (2332320232332).

The spelling of 1211100221211 in words is "one trillion, two hundred eleven billion, one hundred million, two hundred twenty-one thousand, two hundred eleven".