12123410421 has 4 divisors (see below), whose sum is σ = 16164547232. Its totient is φ = 8082273612.

The previous prime is 12123410393. The next prime is 12123410437. The reversal of 12123410421 is 12401432121.

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 not a de Polignac number, because 12123410421 - 2⁷ = 12123410293 is a prime.

It is a super-2 number, since 2×12123410421² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12123412421) 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, 2020568401 + ... + 2020568406.

It is an arithmetic number, because the mean of its divisors is an integer number (4041136808).

Almost surely, 2^12123410421 is an apocalyptic number.

It is an amenable number.

12123410421 is a deficient number, since it is larger than the sum of its proper divisors (4041136811).

12123410421 is an equidigital number, since it uses as much as digits as its factorization.

12123410421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4041136810.

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 12123410421 its reverse (12401432121), we get a palindrome (24524842542).

The spelling of 12123410421 in words is "twelve billion, one hundred twenty-three million, four hundred ten thousand, four hundred twenty-one".