43642640 has 20 divisors (see below), whose sum is σ = 101469324. Its totient is φ = 17457024.

The previous prime is 43642631. The next prime is 43642657. The reversal of 43642640 is 4624634.

It is a happy number.

43642640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 18079504 + 25563136 = 4252^2 + 5056^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 272687 + ... + 272846.

Almost surely, 2^43642640 is an apocalyptic number.

43642640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

43642640 is an abundant number, since it is smaller than the sum of its proper divisors (57826684).

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

43642640 is a wasteful number, since it uses less digits than its factorization.

43642640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545546 (or 545540 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 29.

The square root of 43642640 is about 6606.2576395415. The cubic root of 43642640 is about 352.0764727100.

The spelling of 43642640 in words is "forty-three million, six hundred forty-two thousand, six hundred forty".