2111211211221 has 80 divisors (see below), whose sum is σ = 3619830083584. Its totient is φ = 1201223501856.

The previous prime is 2111211211217. The next prime is 2111211211237. The reversal of 2111211211221 is 1221121121112.

It is a happy number.

2111211211221 is a `hidden beast` number, since 21 + 1 + 1 + 211 + 211 + 221 = 666.

It is not a de Polignac number, because 2111211211221 - 2² = 2111211211217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2111211211194 and 2111211211203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2111211211121) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 247587060 + ... + 247595586.

Almost surely, 2^{2111211211221} is an apocalyptic number.

2111211211221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2111211211221 is a deficient number, since it is larger than the sum of its proper divisors (1508618872363).

2111211211221 is a wasteful number, since it uses less digits than its factorization.

2111211211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10372 (or 10363 counting only the distinct ones).

The product of its digits is 32, while the sum is 18.

Adding to 2111211211221 its reverse (1221121121112), we get a palindrome (3332332332333).

The spelling of 2111211211221 in words is "two trillion, one hundred eleven billion, two hundred eleven million, two hundred eleven thousand, two hundred twenty-one".