1211020222221 has 80 divisors (see below), whose sum is σ = 1867910647680. Its totient is φ = 781634810880.

The previous prime is 1211020222211. The next prime is 1211020222241. The reversal of 1211020222221 is 1222220201121.

It is a happy number.

1211020222221 is a `hidden beast` number, since 121 + 102 + 0 + 222 + 221 = 666.

It is not a de Polignac number, because 1211020222221 - 2⁶ = 1211020222157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211020222194 and 1211020222203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211020222201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 67604256 + ... + 67622166.

It is an arithmetic number, because the mean of its divisors is an integer number (23348883096).

Almost surely, 2^{1211020222221} is an apocalyptic number.

It is an amenable number.

1211020222221 is a deficient number, since it is larger than the sum of its proper divisors (656890425459).

1211020222221 is a wasteful number, since it uses less digits than its factorization.

1211020222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18208 (or 18199 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1211020222221 its reverse (1222220201121), we get a palindrome (2433240423342).

The spelling of 1211020222221 in words is "one trillion, two hundred eleven billion, twenty million, two hundred twenty-two thousand, two hundred twenty-one".