12509555 has 4 divisors (see below), whose sum is σ = 15011472. Its totient is φ = 10007640.

The previous prime is 12509533. The next prime is 12509579. The reversal of 12509555 is 55590521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55590521 = 7 ⋅7941503.

It is a de Polignac number, because none of the positive numbers 2^k-12509555 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1250951 + ... + 1250960.

It is an arithmetic number, because the mean of its divisors is an integer number (3752868).

Almost surely, 2^12509555 is an apocalyptic number.

12509555 is a deficient number, since it is larger than the sum of its proper divisors (2501917).

12509555 is an equidigital number, since it uses as much as digits as its factorization.

12509555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2501916.

The product of its (nonzero) digits is 11250, while the sum is 32.

The square root of 12509555 is about 3536.8849288604. The cubic root of 12509555 is about 232.1385604615.

The spelling of 12509555 in words is "twelve million, five hundred nine thousand, five hundred fifty-five".