123211031221 has 4 divisors (see below), whose sum is σ = 127459687500. Its totient is φ = 118962374944.

The previous prime is 123211031219. The next prime is 123211031233. The reversal of 123211031221 is 122130112321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122130112321 = 7 ⋅17447158903.

It can be written as a sum of positive squares in 2 ways, for example, as 29353968900 + 93857062321 = 171330^2 + 306361^2 .

It is a cyclic number.

It is not a de Polignac number, because 123211031221 - 2¹ = 123211031219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123211031821) 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, 2124328096 + ... + 2124328153.

It is an arithmetic number, because the mean of its divisors is an integer number (31864921875).

Almost surely, 2^123211031221 is an apocalyptic number.

It is an amenable number.

123211031221 is a deficient number, since it is larger than the sum of its proper divisors (4248656279).

123211031221 is an equidigital number, since it uses as much as digits as its factorization.

123211031221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4248656278.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 123211031221 its reverse (122130112321), we get a palindrome (245341143542).

The spelling of 123211031221 in words is "one hundred twenty-three billion, two hundred eleven million, thirty-one thousand, two hundred twenty-one".