12005550 has 48 divisors (see below), whose sum is σ = 33085680. Its totient is φ = 3201120.

The previous prime is 12005537. The next prime is 12005597. The reversal of 12005550 is 5550021.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 3097 + ... + 5796.

It is an arithmetic number, because the mean of its divisors is an integer number (689285).

Almost surely, 2^12005550 is an apocalyptic number.

12005550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12005550 is an abundant number, since it is smaller than the sum of its proper divisors (21080130).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12005550 is a wasteful number, since it uses less digits than its factorization.

12005550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8914 (or 8903 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 18.

The square root of 12005550 is about 3464.9025960335. The cubic root of 12005550 is about 228.9781384265.

Adding to 12005550 its reverse (5550021), we get a palindrome (17555571).

The spelling of 12005550 in words is "twelve million, five thousand, five hundred fifty".