221212323 has 16 divisors (see below), whose sum is σ = 327953440. Its totient is φ = 147370752.

The previous prime is 221212309. The next prime is 221212333. The reversal of 221212323 is 323212122.

It is not a de Polignac number, because 221212323 - 2¹⁴ = 221195939 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221212296 and 221212305.

It is not an unprimeable number, because it can be changed into a prime (221212333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65115 + ... + 68427.

It is an arithmetic number, because the mean of its divisors is an integer number (20497090).

Almost surely, 2^221212323 is an apocalyptic number.

221212323 is a deficient number, since it is larger than the sum of its proper divisors (106741117).

221212323 is a wasteful number, since it uses less digits than its factorization.

221212323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5795 (or 5789 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 221212323 is about 14873.2082282203. The cubic root of 221212323 is about 604.7879164646.

Adding to 221212323 its reverse (323212122), we get a palindrome (544424445).

It can be divided in two parts, 2212 and 12323, that added together give a triangular number (14535 = T₁₇₀).

The spelling of 221212323 in words is "two hundred twenty-one million, two hundred twelve thousand, three hundred twenty-three".