643425930 has 160 divisors (see below), whose sum is σ = 2031359616. Its totient is φ = 143047296.

The previous prime is 643425919. The next prime is 643425931. The reversal of 643425930 is 39524346.

643425930 is a `hidden beast` number, since 64 + 3 + 4 + 2 + 593 + 0 = 666.

643425930 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (643425931) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 208257 + ... + 211323.

Almost surely, 2^643425930 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643425930, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1015679808).

643425930 is an abundant number, since it is smaller than the sum of its proper divisors (1387933686).

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

643425930 is a wasteful number, since it uses less digits than its factorization.

643425930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3130 (or 3121 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The square root of 643425930 is about 25365.8417956117. The cubic root of 643425930 is about 863.3088367138.

The spelling of 643425930 in words is "six hundred forty-three million, four hundred twenty-five thousand, nine hundred thirty".