12606557081 has 4 divisors (see below), whose sum is σ = 12820227600. Its totient is φ = 12392886564.

The previous prime is 12606557063. The next prime is 12606557087. The reversal of 12606557081 is 18075560621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18075560621 = 8429 ⋅2144449.

It is a cyclic number.

It is not a de Polignac number, because 12606557081 - 2⁶ = 12606557017 is a prime.

It is a super-2 number, since 2×12606557081² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12606557087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106835171 + ... + 106835288.

It is an arithmetic number, because the mean of its divisors is an integer number (3205056900).

Almost surely, 2^12606557081 is an apocalyptic number.

It is an amenable number.

12606557081 is a deficient number, since it is larger than the sum of its proper divisors (213670519).

12606557081 is an equidigital number, since it uses as much as digits as its factorization.

12606557081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213670518.

The product of its (nonzero) digits is 100800, while the sum is 41.

The spelling of 12606557081 in words is "twelve billion, six hundred six million, five hundred fifty-seven thousand, eighty-one".