12165555 has 8 divisors (see below), whose sum is σ = 19464912. Its totient is φ = 6488288.

The previous prime is 12165497. The next prime is 12165581. The reversal of 12165555 is 55556121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12165555 - 2⁷ = 12165427 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 405504 + ... + 405533.

It is an arithmetic number, because the mean of its divisors is an integer number (2433114).

Almost surely, 2^12165555 is an apocalyptic number.

12165555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

12165555 is a deficient number, since it is larger than the sum of its proper divisors (7299357).

12165555 is an equidigital number, since it uses as much as digits as its factorization.

12165555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811045.

The product of its digits is 7500, while the sum is 30.

The square root of 12165555 is about 3487.9155666386. The cubic root of 12165555 is about 229.9908944095.

It can be divided in two parts, 12165 and 555, that added together give a triangular number (12720 = T₁₅₉).

The spelling of 12165555 in words is "twelve million, one hundred sixty-five thousand, five hundred fifty-five".