643811436463 has 12 divisors (see below), whose sum is σ = 698065998168. Its totient is φ = 593502305760.

The previous prime is 643811436461. The next prime is 643811436503. The reversal of 643811436463 is 364634118346.

It is not a de Polignac number, because 643811436463 - 2¹ = 643811436461 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 (643811436461) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2388273 + ... + 2644138.

It is an arithmetic number, because the mean of its divisors is an integer number (58172166514).

Almost surely, 2^643811436463 is an apocalyptic number.

643811436463 is a deficient number, since it is larger than the sum of its proper divisors (54254561705).

643811436463 is a wasteful number, since it uses less digits than its factorization.

643811436463 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5033194 (or 5033181 counting only the distinct ones).

The product of its digits is 2985984, while the sum is 49.

The spelling of 643811436463 in words is "six hundred forty-three billion, eight hundred eleven million, four hundred thirty-six thousand, four hundred sixty-three".