643075718840 has 16 divisors (see below), whose sum is σ = 1446920367480. Its totient is φ = 257230287520.

The previous prime is 643075718801. The next prime is 643075718927. The reversal of 643075718840 is 48817570346.

It is a happy 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, 8038446446 + ... + 8038446525.

Almost surely, 2^643075718840 is an apocalyptic number.

It is an amenable number.

643075718840 is an abundant number, since it is smaller than the sum of its proper divisors (803844648640).

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

643075718840 is a wasteful number, since it uses less digits than its factorization.

643075718840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16076892982 (or 16076892978 counting only the distinct ones).

The product of its (nonzero) digits is 4515840, while the sum is 53.

The spelling of 643075718840 in words is "six hundred forty-three billion, seventy-five million, seven hundred eighteen thousand, eight hundred forty".