643523019863 has 4 divisors (see below), whose sum is σ = 655664963688. Its totient is φ = 631381076040.

The previous prime is 643523019787. The next prime is 643523019871. The reversal of 643523019863 is 368910325346.

643523019863 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 643523019863 - 2¹⁰ = 643523018839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643523019163) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6070971833 + ... + 6070971938.

It is an arithmetic number, because the mean of its divisors is an integer number (163916240922).

Almost surely, 2^643523019863 is an apocalyptic number.

643523019863 is a deficient number, since it is larger than the sum of its proper divisors (12141943825).

643523019863 is a wasteful number, since it uses less digits than its factorization.

643523019863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12141943824.

The product of its (nonzero) digits is 2799360, while the sum is 50.

The spelling of 643523019863 in words is "six hundred forty-three billion, five hundred twenty-three million, nineteen thousand, eight hundred sixty-three".