643554803694 has 32 divisors (see below), whose sum is σ = 1405235018880. Its totient is φ = 194861684000.

The previous prime is 643554803653. The next prime is 643554803713. The reversal of 643554803694 is 496308455346.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3789357 + ... + 3955544.

It is an arithmetic number, because the mean of its divisors is an integer number (43913594340).

Almost surely, 2^643554803694 is an apocalyptic number.

643554803694 is an abundant number, since it is smaller than the sum of its proper divisors (761680215186).

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

643554803694 is a wasteful number, since it uses less digits than its factorization.

643554803694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7746176.

The product of its (nonzero) digits is 37324800, while the sum is 57.

The spelling of 643554803694 in words is "six hundred forty-three billion, five hundred fifty-four million, eight hundred three thousand, six hundred ninety-four".