12523442421 has 32 divisors (see below), whose sum is σ = 19566976000. Its totient is φ = 6975569664.

The previous prime is 12523442419. The next prime is 12523442453. The reversal of 12523442421 is 12424432521.

It is a happy number.

It is not a de Polignac number, because 12523442421 - 2¹ = 12523442419 is a prime.

It is a super-2 number, since 2×12523442421² (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 (12523442461) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 436701 + ... + 464493.

It is an arithmetic number, because the mean of its divisors is an integer number (611468000).

Almost surely, 2^12523442421 is an apocalyptic number.

It is an amenable number.

12523442421 is a deficient number, since it is larger than the sum of its proper divisors (7043533579).

12523442421 is a wasteful number, since it uses less digits than its factorization.

12523442421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28345.

The product of its digits is 15360, while the sum is 30.

Adding to 12523442421 its reverse (12424432521), we get a palindrome (24947874942).

The spelling of 12523442421 in words is "twelve billion, five hundred twenty-three million, four hundred forty-two thousand, four hundred twenty-one".