640986665080 has 16 divisors (see below), whose sum is σ = 1442219996520. Its totient is φ = 256394666016.

The previous prime is 640986665071. The next prime is 640986665083. The reversal of 640986665080 is 80566689046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640986665083) 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, 8012333274 + ... + 8012333353.

Almost surely, 2^640986665080 is an apocalyptic number.

It is an amenable number.

640986665080 is an abundant number, since it is smaller than the sum of its proper divisors (801233331440).

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

640986665080 is a wasteful number, since it uses less digits than its factorization.

640986665080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16024666638 (or 16024666634 counting only the distinct ones).

The product of its (nonzero) digits is 14929920, while the sum is 58.

The spelling of 640986665080 in words is "six hundred forty billion, nine hundred eighty-six million, six hundred sixty-five thousand, eighty".