643946934 has 8 divisors (see below), whose sum is σ = 1287893880. Its totient is φ = 214648976.

The previous prime is 643946923. The next prime is 643946971. The reversal of 643946934 is 439649346.

It is a sphenic number, since it is the product of 3 distinct primes.

643946934 is an admirable number.

It is a Curzon number.

It is a congruent number.

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, 53662239 + ... + 53662250.

It is an arithmetic number, because the mean of its divisors is an integer number (160986735).

Almost surely, 2^643946934 is an apocalyptic number.

643946934 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

643946934 is a wasteful number, since it uses less digits than its factorization.

643946934 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107324494.

The product of its digits is 1679616, while the sum is 48.

The square root of 643946934 is about 25376.1095126893. The cubic root of 643946934 is about 863.5417907535.

The spelling of 643946934 in words is "six hundred forty-three million, nine hundred forty-six thousand, nine hundred thirty-four".