12109505 has 4 divisors (see below), whose sum is σ = 14531412. Its totient is φ = 9687600.

The previous prime is 12109483. The next prime is 12109507. The reversal of 12109505 is 50590121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8690704 + 3418801 = 2948^2 + 1849^2 .

It is a de Polignac number, because none of the positive numbers 2^k-12109505 is a prime.

It is a super-2 number, since 2×12109505² = 293280222690050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12109507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1210946 + ... + 1210955.

It is an arithmetic number, because the mean of its divisors is an integer number (3632853).

Almost surely, 2^12109505 is an apocalyptic number.

It is an amenable number.

12109505 is a deficient number, since it is larger than the sum of its proper divisors (2421907).

12109505 is an equidigital number, since it uses as much as digits as its factorization.

12109505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2421906.

The product of its (nonzero) digits is 450, while the sum is 23.

The square root of 12109505 is about 3479.8714056700. The cubic root of 12109505 is about 229.6371405012.

Adding to 12109505 its reverse (50590121), we get a palindrome (62699626).

The spelling of 12109505 in words is "twelve million, one hundred nine thousand, five hundred five".