43391840 has 48 divisors (see below), whose sum is σ = 103547808. Its totient is φ = 17181696.

The previous prime is 43391833. The next prime is 43391849. The reversal of 43391840 is 4819334.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 43391797 and 43391806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43391849) 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, 15164 + ... + 17796.

It is an arithmetic number, because the mean of its divisors is an integer number (2157246).

Almost surely, 2^43391840 is an apocalyptic number.

43391840 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 43391840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51773904).

43391840 is an abundant number, since it is smaller than the sum of its proper divisors (60155968).

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

43391840 is a wasteful number, since it uses less digits than its factorization.

43391840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2751 (or 2743 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 43391840 is about 6587.2482874111. The cubic root of 43391840 is about 351.4007538359.

The spelling of 43391840 in words is "forty-three million, three hundred ninety-one thousand, eight hundred forty".