641766516636 has 48 divisors (see below), whose sum is σ = 1770390397440. Its totient is φ = 177039038400.

The previous prime is 641766516619. The next prime is 641766516637. The reversal of 641766516636 is 636615667146.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641766516637) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 131723040 + ... + 131727911.

It is an arithmetic number, because the mean of its divisors is an integer number (36883133280).

Almost surely, 2^641766516636 is an apocalyptic number.

It is an amenable number.

641766516636 is an abundant number, since it is smaller than the sum of its proper divisors (1128623880804).

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

641766516636 is a wasteful number, since it uses less digits than its factorization.

641766516636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263450994 (or 263450992 counting only the distinct ones).

The product of its digits is 19595520, while the sum is 57.

The spelling of 641766516636 in words is "six hundred forty-one billion, seven hundred sixty-six million, five hundred sixteen thousand, six hundred thirty-six".