212222121 has 8 divisors (see below), whose sum is σ = 290610624. Its totient is φ = 137657520.

The previous prime is 212222113. The next prime is 212222149. The reversal of 212222121 is 121222212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 212222121 - 2³ = 212222113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212222121.

It is not an unprimeable number, because it can be changed into a prime (212222321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 955845 + ... + 956066.

It is an arithmetic number, because the mean of its divisors is an integer number (36326328).

Almost surely, 2^212222121 is an apocalyptic number.

It is an amenable number.

212222121 is a deficient number, since it is larger than the sum of its proper divisors (78388503).

212222121 is a wasteful number, since it uses less digits than its factorization.

212222121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1911951.

The product of its digits is 64, while the sum is 15.

The square root of 212222121 is about 14567.8454481093. The cubic root of 212222121 is about 596.4813696258.

Adding to 212222121 its reverse (121222212), we get a palindrome (333444333).

Subtracting from 212222121 its reverse (121222212), we obtain a palindrome (90999909).

The spelling of 212222121 in words is "two hundred twelve million, two hundred twenty-two thousand, one hundred twenty-one".