12557075521 has 2 divisors, whose sum is σ = 12557075522. Its totient is φ = 12557075520.

The previous prime is 12557075519. The next prime is 12557075527.

It is a happy number.

12557075521 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11543353600 + 1013721921 = 107440^2 + 31839^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 12557075521 - 2¹ = 12557075519 is a prime.

Together with 12557075519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (12557075527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6278537760 + 6278537761.

It is an arithmetic number, because the mean of its divisors is an integer number (6278537761).

Almost surely, 2^12557075521 is an apocalyptic number.

It is an amenable number.

12557075521 is a deficient number, since it is larger than the sum of its proper divisors (1).

12557075521 is an equidigital number, since it uses as much as digits as its factorization.

12557075521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122500, while the sum is 40.

The spelling of 12557075521 in words is "twelve billion, five hundred fifty-seven million, seventy-five thousand, five hundred twenty-one".