212111321 has 4 divisors (see below), whose sum is σ = 213337572. Its totient is φ = 210885072.

The previous prime is 212111309. The next prime is 212111323. The reversal of 212111321 is 123111212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 192654400 + 19456921 = 13880^2 + 4411^2 .

It is a cyclic number.

It is not a de Polignac number, because 212111321 - 2⁶ = 212111257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212111296 and 212111305.

It is not an unprimeable number, because it can be changed into a prime (212111323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 612866 + ... + 613211.

It is an arithmetic number, because the mean of its divisors is an integer number (53334393).

Almost surely, 2^212111321 is an apocalyptic number.

It is an amenable number.

212111321 is a deficient number, since it is larger than the sum of its proper divisors (1226251).

212111321 is a wasteful number, since it uses less digits than its factorization.

212111321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1226250.

The product of its digits is 24, while the sum is 14.

The square root of 212111321 is about 14564.0420556932. The cubic root of 212111321 is about 596.3775450095.

Adding to 212111321 its reverse (123111212), we get a palindrome (335222533).

The spelling of 212111321 in words is "two hundred twelve million, one hundred eleven thousand, three hundred twenty-one".