12558171421 has 4 divisors (see below), whose sum is σ = 12638159932. Its totient is φ = 12478182912.

The previous prime is 12558171403. The next prime is 12558171433. The reversal of 12558171421 is 12417185521.

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 8536836025 + 4021335396 = 92395^2 + 63414^2 .

It is a cyclic number.

It is not a de Polignac number, because 12558171421 - 2⁹ = 12558170909 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 (12558171491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39994020 + ... + 39994333.

It is an arithmetic number, because the mean of its divisors is an integer number (3159539983).

Almost surely, 2^12558171421 is an apocalyptic number.

It is an amenable number.

12558171421 is a deficient number, since it is larger than the sum of its proper divisors (79988511).

12558171421 is an equidigital number, since it uses as much as digits as its factorization.

12558171421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79988510.

The product of its digits is 22400, while the sum is 37.

The spelling of 12558171421 in words is "twelve billion, five hundred fifty-eight million, one hundred seventy-one thousand, four hundred twenty-one".