12400438 has 4 divisors (see below), whose sum is σ = 18600660. Its totient is φ = 6200218.

The previous prime is 12400397. The next prime is 12400441. The reversal of 12400438 is 83400421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83400421 = 13 ⋅6415417.

It is a super-3 number, since 3×12400438³ (a number of 22 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3100108 + ... + 3100111.

It is an arithmetic number, because the mean of its divisors is an integer number (4650165).

Almost surely, 2^12400438 is an apocalyptic number.

12400438 is a deficient number, since it is larger than the sum of its proper divisors (6200222).

12400438 is an equidigital number, since it uses as much as digits as its factorization.

12400438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6200221.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 12400438 is about 3521.4255636035. The cubic root of 12400438 is about 231.4616306625.

Adding to 12400438 its reverse (83400421), we get a palindrome (95800859).

The spelling of 12400438 in words is "twelve million, four hundred thousand, four hundred thirty-eight".