640032568066 has 8 divisors (see below), whose sum is σ = 993153985020. Its totient is φ = 308981239728.

The previous prime is 640032568031. The next prime is 640032568079. The reversal of 640032568066 is 660865230046.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 593240388841 + 46792179225 = 770221^2 + 216315^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5517522081 + ... + 5517522196.

Almost surely, 2^640032568066 is an apocalyptic number.

640032568066 is a deficient number, since it is larger than the sum of its proper divisors (353121416954).

640032568066 is a wasteful number, since it uses less digits than its factorization.

640032568066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11035044308.

The product of its (nonzero) digits is 1244160, while the sum is 46.

The spelling of 640032568066 in words is "six hundred forty billion, thirty-two million, five hundred sixty-eight thousand, sixty-six".