43243840 has 56 divisors (see below), whose sum is σ = 103537512. Its totient is φ = 17203200.

The previous prime is 43243831. The next prime is 43243847. The reversal of 43243840 is 4834234.

It can be written as a sum of positive squares in 4 ways, for example, as 11614464 + 31629376 = 3408^2 + 5624^2 .

It is a junction number, because it is equal to n+sod(n) for n = 43243799 and 43243808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43243847) 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, 107640 + ... + 108040.

Almost surely, 2^43243840 is an apocalyptic number.

43243840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 43243840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51768756).

43243840 is an abundant number, since it is smaller than the sum of its proper divisors (60293672).

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

43243840 is a wasteful number, since it uses less digits than its factorization.

43243840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755 (or 745 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

The square root of 43243840 is about 6576.0048661782. The cubic root of 43243840 is about 351.0007819183. Note that the first 3 decimals are identical.

The spelling of 43243840 in words is "forty-three million, two hundred forty-three thousand, eight hundred forty".