43685640 has 48 divisors (see below), whose sum is σ = 141979500. Its totient is φ = 11649408.

The previous prime is 43685627. The next prime is 43685683. The reversal of 43685640 is 4658634.

43685640 is a `hidden beast` number, since 4 + 3 + 6 + 8 + 5 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 40678884 + 3006756 = 6378^2 + 1734^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 43685595 and 43685604.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 60315 + ... + 61034.

Almost surely, 2^43685640 is an apocalyptic number.

43685640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

43685640 is an abundant number, since it is smaller than the sum of its proper divisors (98293860).

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

43685640 is a wasteful number, since it uses less digits than its factorization.

43685640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121366 (or 121359 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 43685640 is about 6609.5113283812. The cubic root of 43685640 is about 352.1920654646.

The spelling of 43685640 in words is "forty-three million, six hundred eighty-five thousand, six hundred forty".