12400243 has 4 divisors (see below), whose sum is σ = 12939408. Its totient is φ = 11861080.

The previous prime is 12400237. The next prime is 12400247. The reversal of 12400243 is 34200421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34200421 = 463 ⋅73867.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12400243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12400247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 269548 + ... + 269593.

It is an arithmetic number, because the mean of its divisors is an integer number (3234852).

Almost surely, 2^12400243 is an apocalyptic number.

12400243 is a deficient number, since it is larger than the sum of its proper divisors (539165).

12400243 is an equidigital number, since it uses as much as digits as its factorization.

12400243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539164.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 12400243 is about 3521.3978758442. The cubic root of 12400243 is about 231.4604173920.

Adding to 12400243 its reverse (34200421), we get a palindrome (46600664).

The spelling of 12400243 in words is "twelve million, four hundred thousand, two hundred forty-three".