643430 has 24 divisors (see below), whose sum is σ = 1215648. Its totient is φ = 245088.

The previous prime is 643429. The next prime is 643439. The reversal of 643430 is 34346.

It is a happy number.

643430 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 not an unprimeable number, because it can be changed into a prime (643439) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13667 + ... + 13713.

It is an arithmetic number, because the mean of its divisors is an integer number (50652).

2⁶⁴³⁴³⁰ is an apocalyptic number.

643430 is a deficient number, since it is larger than the sum of its proper divisors (572218).

643430 is a wasteful number, since it uses less digits than its factorization.

643430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 20.

The square root of 643430 is about 802.1408853811. The cubic root of 643430 is about 86.3310657001.

Adding to 643430 its reverse (34346), we get a palindrome (677776).

The spelling of 643430 in words is "six hundred forty-three thousand, four hundred thirty".