640108068 has 48 divisors (see below), whose sum is σ = 1548482880. Its totient is φ = 205559424.

The previous prime is 640108061. The next prime is 640108069. The reversal of 640108068 is 860801046.

It is not an unprimeable number, because it can be changed into a prime (640108061) 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, 180246 + ... + 183762.

It is an arithmetic number, because the mean of its divisors is an integer number (32260060).

Almost surely, 2^640108068 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640108068, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (774241440).

640108068 is an abundant number, since it is smaller than the sum of its proper divisors (908374812).

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

640108068 is a wasteful number, since it uses less digits than its factorization.

640108068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4076 (or 4074 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 640108068 is about 25300.3570725790. The cubic root of 640108068 is about 861.8223785846.

The spelling of 640108068 in words is "six hundred forty million, one hundred eight thousand, sixty-eight".