1221212012211 has 6 divisors (see below), whose sum is σ = 1763972906540. Its totient is φ = 814141341468.

The previous prime is 1221212012201. The next prime is 1221212012219. The reversal of 1221212012211 is 1122102121221.

1221212012211 is a `hidden beast` number, since 1 + 221 + 21 + 201 + 221 + 1 = 666.

It is not a de Polignac number, because 1221212012211 - 2¹¹ = 1221212010163 is a prime.

It is a super-2 number, since 2×1221212012211² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221212012219) 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 5 ways as a sum of consecutive naturals, for example, 67845111781 + ... + 67845111798.

Almost surely, 2^{1221212012211} is an apocalyptic number.

1221212012211 is a deficient number, since it is larger than the sum of its proper divisors (542760894329).

1221212012211 is a wasteful number, since it uses less digits than its factorization.

1221212012211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135690223585 (or 135690223582 counting only the distinct ones).

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

Adding to 1221212012211 its reverse (1122102121221), we get a palindrome (2343314133432).

The spelling of 1221212012211 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, twelve thousand, two hundred eleven".