643566542 has 16 divisors (see below), whose sum is σ = 1014684192. Its totient is φ = 305543040.

The previous prime is 643566529. The next prime is 643566559. The reversal of 643566542 is 245665346.

It is a happy number.

643566542 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 643566542.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44759 + ... + 57362.

It is an arithmetic number, because the mean of its divisors is an integer number (63417762).

Almost surely, 2^643566542 is an apocalyptic number.

643566542 is a deficient number, since it is larger than the sum of its proper divisors (371117650).

643566542 is a wasteful number, since it uses less digits than its factorization.

643566542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102283.

The product of its digits is 518400, while the sum is 41.

The square root of 643566542 is about 25368.6133243423. The cubic root of 643566542 is about 863.3717202744.

The spelling of 643566542 in words is "six hundred forty-three million, five hundred sixty-six thousand, five hundred forty-two".