1211210221011 has 192 divisors, whose sum is σ = 2088486420480. Its totient is φ = 619636469760.

The previous prime is 1211210221009. The next prime is 1211210221019. The reversal of 1211210221011 is 1101220121121.

It is a happy number.

It is not a de Polignac number, because 1211210221011 - 2¹ = 1211210221009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211210221019) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 2616004566 + ... + 2616005028.

It is an arithmetic number, because the mean of its divisors is an integer number (10877533440).

Almost surely, 2^{1211210221011} is an apocalyptic number.

1211210221011 is a deficient number, since it is larger than the sum of its proper divisors (877276199469).

1211210221011 is a wasteful number, since it uses less digits than its factorization.

1211210221011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926 (or 919 counting only the distinct ones).

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

Adding to 1211210221011 its reverse (1101220121121), we get a palindrome (2312430342132).

The spelling of 1211210221011 in words is "one trillion, two hundred eleven billion, two hundred ten million, two hundred twenty-one thousand, eleven".