212121233 has 4 divisors (see below), whose sum is σ = 215108928. Its totient is φ = 209133540.

The previous prime is 212121209. The next prime is 212121289. The reversal of 212121233 is 332121212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 212121233 - 2⁸ = 212120977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212127233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1493741 + ... + 1493882.

It is an arithmetic number, because the mean of its divisors is an integer number (53777232).

Almost surely, 2^212121233 is an apocalyptic number.

It is an amenable number.

212121233 is a deficient number, since it is larger than the sum of its proper divisors (2987695).

212121233 is an equidigital number, since it uses as much as digits as its factorization.

212121233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2987694.

The product of its digits is 144, while the sum is 17.

The square root of 212121233 is about 14564.3823418640. The cubic root of 212121233 is about 596.3868344746.

Adding to 212121233 its reverse (332121212), we get a palindrome (544242445).

It can be divided in two parts, 2121212 and 33, that multiplied together give a palindrome (69999996).

The spelling of 212121233 in words is "two hundred twelve million, one hundred twenty-one thousand, two hundred thirty-three".