12400304021 has 6 divisors (see below), whose sum is σ = 14424843510. Its totient is φ = 10628831976.

The previous prime is 12400304011. The next prime is 12400304023. The reversal of 12400304021 is 12040300421.

It can be written as a sum of positive squares in only one way, i.e., 6446484100 + 5953819921 = 80290^2 + 77161^2 .

It is not a de Polignac number, because 12400304021 - 2¹⁰ = 12400302997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12400304023) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 126533666 + ... + 126533763.

It is an arithmetic number, because the mean of its divisors is an integer number (2404140585).

Almost surely, 2^12400304021 is an apocalyptic number.

It is an amenable number.

12400304021 is a deficient number, since it is larger than the sum of its proper divisors (2024539489).

12400304021 is an equidigital number, since it uses as much as digits as its factorization.

12400304021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253067443 (or 253067436 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 12400304021 its reverse (12040300421), we get a palindrome (24440604442).

The spelling of 12400304021 in words is "twelve billion, four hundred million, three hundred four thousand, twenty-one".