211212212121 has 32 divisors (see below), whose sum is σ = 316077632640. Its totient is φ = 139381992000.

The previous prime is 211212212089. The next prime is 211212212131. The reversal of 211212212121 is 121212212112.

211212212121 is a `hidden beast` number, since 211 + 21 + 221 + 212 + 1 = 666.

It is not a de Polignac number, because 211212212121 - 2⁵ = 211212212089 is a prime.

It is a super-2 number, since 2×211212212121² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 211212212094 and 211212212103.

It is not an unprimeable number, because it can be changed into a prime (211212212131) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20777386 + ... + 20787548.

It is an arithmetic number, because the mean of its divisors is an integer number (9877426020).

Almost surely, 2^211212212121 is an apocalyptic number.

It is an amenable number.

211212212121 is a deficient number, since it is larger than the sum of its proper divisors (104865420519).

211212212121 is a wasteful number, since it uses less digits than its factorization.

211212212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17894 (or 17888 counting only the distinct ones).

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

Adding to 211212212121 its reverse (121212212112), we get a palindrome (332424424233).

Subtracting from 211212212121 its reverse (121212212112), we obtain a palindrome (90000000009).

The spelling of 211212212121 in words is "two hundred eleven billion, two hundred twelve million, two hundred twelve thousand, one hundred twenty-one".