12125430021 has 4 divisors (see below), whose sum is σ = 16167240032. Its totient is φ = 8083620012.

The previous prime is 12125430019. The next prime is 12125430059. The reversal of 12125430021 is 12003452121.

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 12125430021 - 2¹ = 12125430019 is a prime.

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 12125430021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12125430061) 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, 2020905001 + ... + 2020905006.

It is an arithmetic number, because the mean of its divisors is an integer number (4041810008).

Almost surely, 2^12125430021 is an apocalyptic number.

It is an amenable number.

12125430021 is a deficient number, since it is larger than the sum of its proper divisors (4041810011).

12125430021 is an equidigital number, since it uses as much as digits as its factorization.

12125430021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4041810010.

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 12125430021 its reverse (12003452121), we get a palindrome (24128882142).

The spelling of 12125430021 in words is "twelve billion, one hundred twenty-five million, four hundred thirty thousand, twenty-one".