640335800 has 96 divisors (see below), whose sum is σ = 1620469200. Its totient is φ = 233902080.

The previous prime is 640335797. The next prime is 640335809. The reversal of 640335800 is 8533046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640335809) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 250931 + ... + 253469.

Almost surely, 2^640335800 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 640335800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (810234600).

640335800 is an abundant number, since it is smaller than the sum of its proper divisors (980133400).

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

640335800 is a wasteful number, since it uses less digits than its factorization.

640335800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2665 (or 2656 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 640335800 is about 25304.8572412492. The cubic root of 640335800 is about 861.9245703202.

Adding to 640335800 its reverse (8533046), we get a palindrome (648868846).

The spelling of 640335800 in words is "six hundred forty million, three hundred thirty-five thousand, eight hundred".