643776011686 has 8 divisors (see below), whose sum is σ = 1022467783320. Its totient is φ = 302953417248.

The previous prime is 643776011657. The next prime is 643776011699. The reversal of 643776011686 is 686110677346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9467294256 + ... + 9467294323.

It is an arithmetic number, because the mean of its divisors is an integer number (127808472915).

Almost surely, 2^643776011686 is an apocalyptic number.

643776011686 is a deficient number, since it is larger than the sum of its proper divisors (378691771634).

643776011686 is a wasteful number, since it uses less digits than its factorization.

643776011686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18934588598.

The product of its (nonzero) digits is 6096384, while the sum is 55.

It can be divided in two parts, 6437760 and 11686, that added together give a palindrome (6449446).

The spelling of 643776011686 in words is "six hundred forty-three billion, seven hundred seventy-six million, eleven thousand, six hundred eighty-six".