643512 has 16 divisors (see below), whose sum is σ = 1608840. Its totient is φ = 214496.

The previous prime is 643507. The next prime is 643523. The reversal of 643512 is 215346.

It is a happy number.

643512 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 643512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13383 + ... + 13430.

2⁶⁴³⁵¹² is an apocalyptic number.

It is an amenable number.

643512 is an abundant number, since it is smaller than the sum of its proper divisors (965328).

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

643512 is a wasteful number, since it uses less digits than its factorization.

643512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26822 (or 26818 counting only the distinct ones).

The product of its digits is 720, while the sum is 21.

The square root of 643512 is about 802.1919969683. The cubic root of 643512 is about 86.3347329452.

Adding to 643512 its reverse (215346), we get a palindrome (858858).

The spelling of 643512 in words is "six hundred forty-three thousand, five hundred twelve".