123312221 has 4 divisors (see below), whose sum is σ = 123841692. Its totient is φ = 122782752.

The previous prime is 123312199. The next prime is 123312253. The reversal of 123312221 is 122213321.

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 64176121 + 59136100 = 8011^2 + 7690^2 .

It is a cyclic number.

It is not a de Polignac number, because 123312221 - 2¹⁸ = 123050077 is a prime.

It is a super-3 number, since 3×123312221³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 123312221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123312421) 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, 264386 + ... + 264851.

It is an arithmetic number, because the mean of its divisors is an integer number (30960423).

Almost surely, 2^123312221 is an apocalyptic number.

It is an amenable number.

123312221 is a deficient number, since it is larger than the sum of its proper divisors (529471).

123312221 is an equidigital number, since it uses as much as digits as its factorization.

123312221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529470.

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

The square root of 123312221 is about 11104.6035949060. The cubic root of 123312221 is about 497.7394229858.

Adding to 123312221 its reverse (122213321), we get a palindrome (245525542).

The spelling of 123312221 in words is "one hundred twenty-three million, three hundred twelve thousand, two hundred twenty-one".