12507507421 has 2 divisors, whose sum is σ = 12507507422. Its totient is φ = 12507507420.

The previous prime is 12507507401. The next prime is 12507507499. The reversal of 12507507421 is 12470570521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11112111396 + 1395396025 = 105414^2 + 37355^2 .

It is an emirp because it is prime and its reverse (12470570521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12507507421 - 2⁷ = 12507507293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12507507401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6253753710 + 6253753711.

It is an arithmetic number, because the mean of its divisors is an integer number (6253753711).

Almost surely, 2^12507507421 is an apocalyptic number.

It is an amenable number.

12507507421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12507507421 is an equidigital number, since it uses as much as digits as its factorization.

12507507421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19600, while the sum is 34.

The spelling of 12507507421 in words is "twelve billion, five hundred seven million, five hundred seven thousand, four hundred twenty-one".