12405438 has 24 divisors (see below), whose sum is σ = 27088776. Its totient is φ = 4102800.

The previous prime is 12405433. The next prime is 12405467. The reversal of 12405438 is 83450421.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12405431) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 273 + ... + 4988.

It is an arithmetic number, because the mean of its divisors is an integer number (1128699).

Almost surely, 2^12405438 is an apocalyptic number.

12405438 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12405438 is an abundant number, since it is smaller than the sum of its proper divisors (14683338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12405438 is a wasteful number, since it uses less digits than its factorization.

12405438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5400 (or 5397 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 12405438 is about 3522.1354318084. The cubic root of 12405438 is about 231.4927358175.

Adding to 12405438 its reverse (83450421), we get a palindrome (95855859).

It can be divided in two parts, 12 and 405438, that added together give a triangular number (405450 = T₉₀₀).

The spelling of 12405438 in words is "twelve million, four hundred five thousand, four hundred thirty-eight".