12405 has 8 divisors (see below), whose sum is σ = 19872. Its totient is φ = 6608.

The previous prime is 12401. The next prime is 12409. The reversal of 12405 is 50421.

12405 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (12401) and next prime (12409).

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 12405 - 2² = 12401 is a prime.

It is a nialpdrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 399 + ... + 428.

It is an arithmetic number, because the mean of its divisors is an integer number (2484).

2¹²⁴⁰⁵ is an apocalyptic number.

12405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12405 is a deficient number, since it is larger than the sum of its proper divisors (7467).

12405 is an equidigital number, since it uses as much as digits as its factorization.

12405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835.

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 12405 is about 111.3777356566. The cubic root of 12405 is about 23.1490011340.

Adding to 12405 its reverse (50421), we get a palindrome (62826).

The spelling of 12405 in words is "twelve thousand, four hundred five".