12403 has 4 divisors (see below), whose sum is σ = 12640. Its totient is φ = 12168.

The previous prime is 12401. The next prime is 12409. The reversal of 12403 is 30421.

12403 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

12403 is a nontrivial binomial coefficient, being equal to C(158, 2).

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30421 = 29 ⋅1049.

It is a 3-Lehmer number, since φ(12403) divides (12403-1)³.

It is a cyclic number.

It is not a de Polignac number, because 12403 - 2¹ = 12401 is a prime.

It is a deceptive number, since it divides R₁₂₄₀₂.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 12403.

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 3 ways as a sum of consecutive naturals, for example, 1 + ... + 157.

It is an arithmetic number, because the mean of its divisors is an integer number (3160).

2¹²⁴⁰³ is an apocalyptic number.

12403 is the 157-th triangular number and also the 79-th hexagonal number.

12403 is the 53-rd centered nonagonal number.

12403 is a deficient number, since it is larger than the sum of its proper divisors (237).

12403 is an equidigital number, since it uses as much as digits as its factorization.

12403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236.

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 12403 is about 111.3687568396. The cubic root of 12403 is about 23.1477569988.

Adding to 12403 its reverse (30421), we get a palindrome (42824).

The spelling of 12403 in words is "twelve thousand, four hundred three", and thus it is an iban number.