643529694 has 16 divisors (see below), whose sum is σ = 1287936000. Its totient is φ = 214363800.

The previous prime is 643529693. The next prime is 643529717. The reversal of 643529694 is 496925346.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643529693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26782 + ... + 44769.

It is an arithmetic number, because the mean of its divisors is an integer number (80496000).

Almost surely, 2^643529694 is an apocalyptic number.

643529694 is an abundant number, since it is smaller than the sum of its proper divisors (644406306).

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

643529694 is a wasteful number, since it uses less digits than its factorization.

643529694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73055.

The product of its digits is 1399680, while the sum is 48.

The square root of 643529694 is about 25367.8870621895. The cubic root of 643529694 is about 863.3552422433.

The spelling of 643529694 in words is "six hundred forty-three million, five hundred twenty-nine thousand, six hundred ninety-four".