43646643 has 12 divisors (see below), whose sum is σ = 64749568. Its totient is φ = 28311120.

The previous prime is 43646639. The next prime is 43646657. The reversal of 43646643 is 34664634.

43646643 is a `hidden beast` number, since 4 + 3 + 6 + 4 + 6 + 643 = 666.

It is not a de Polignac number, because 43646643 - 2² = 43646639 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43646598 and 43646607.

It is not an unprimeable number, because it can be changed into a prime (43646623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65203 + ... + 65868.

Almost surely, 2^43646643 is an apocalyptic number.

43646643 is a deficient number, since it is larger than the sum of its proper divisors (21102925).

43646643 is a wasteful number, since it uses less digits than its factorization.

43646643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131114 (or 131111 counting only the distinct ones).

The product of its digits is 124416, while the sum is 36.

The square root of 43646643 is about 6606.5606029159. The cubic root of 43646643 is about 352.0872367933.

Subtracting from 43646643 its reverse (34664634), we obtain a square (8982009 = 2997²).

The spelling of 43646643 in words is "forty-three million, six hundred forty-six thousand, six hundred forty-three".