43431440 has 40 divisors (see below), whose sum is σ = 108748248. Its totient is φ = 16035840.

The previous prime is 43431389. The next prime is 43431449. The reversal of 43431440 is 4413434.

It can be written as a sum of positive squares in 4 ways, for example, as 2930944 + 40500496 = 1712^2 + 6364^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (43431449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19841 + ... + 21920.

Almost surely, 2^43431440 is an apocalyptic number.

43431440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

43431440 is an abundant number, since it is smaller than the sum of its proper divisors (65316808).

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

43431440 is a wasteful number, since it uses less digits than its factorization.

43431440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41787 (or 41781 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 23.

The square root of 43431440 is about 6590.2534093918. The cubic root of 43431440 is about 351.5076190810.

Adding to 43431440 its reverse (4413434), we get a palindrome (47844874).

The spelling of 43431440 in words is "forty-three million, four hundred thirty-one thousand, four hundred forty".