12131305 has 8 divisors (see below), whose sum is σ = 14708232. Its totient is φ = 9604608.

The previous prime is 12131303. The next prime is 12131321. The reversal of 12131305 is 50313121.

It can be written as a sum of positive squares in 4 ways, for example, as 4380649 + 7750656 = 2093^2 + 2784^2 .

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 12131305 - 2¹ = 12131303 is a prime.

It is a super-2 number, since 2×12131305² = 294337122006050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12131303) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12022 + ... + 12991.

It is an arithmetic number, because the mean of its divisors is an integer number (1838529).

Almost surely, 2^12131305 is an apocalyptic number.

It is an amenable number.

12131305 is a deficient number, since it is larger than the sum of its proper divisors (2576927).

12131305 is an equidigital number, since it uses as much as digits as its factorization.

12131305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25115.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 12131305 is about 3483.0022968698. The cubic root of 12131305 is about 229.7748584511.

Subtracting from 12131305 its sum of digits (16), we obtain a square (12131289 = 3483²).

Adding to 12131305 its reverse (50313121), we get a palindrome (62444426).

The spelling of 12131305 in words is "twelve million, one hundred thirty-one thousand, three hundred five".