643930 has 16 divisors (see below), whose sum is σ = 1324800. Its totient is φ = 220752.

The previous prime is 643927. The next prime is 643949. The reversal of 643930 is 39346.

643930 is nontrivially palindromic in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 643895 and 643904.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4530 + ... + 4669.

It is an arithmetic number, because the mean of its divisors is an integer number (82800).

2⁶⁴³⁹³⁰ is an apocalyptic number.

643930 is an abundant number, since it is smaller than the sum of its proper divisors (680870).

It is a weird number, because it is abundant, but not a pseudoperfect number.

643930 is a wasteful number, since it uses less digits than its factorization.

643930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9213.

The product of its (nonzero) digits is 1944, while the sum is 25.

The square root of 643930 is about 802.4524908055. The cubic root of 643930 is about 86.3534221111.

The spelling of 643930 in words is "six hundred forty-three thousand, nine hundred thirty".