640704200 has 48 divisors (see below), whose sum is σ = 1495300500. Its totient is φ = 255307520.

The previous prime is 640704193. The next prime is 640704209. The reversal of 640704200 is 2407046.

It can be written as a sum of positive squares in 6 ways, for example, as 54967396 + 585736804 = 7414^2 + 24202^2 .

It is not an unprimeable number, because it can be changed into a prime (640704209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 47846 + ... + 59754.

Almost surely, 2^640704200 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 640704200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (747650250).

640704200 is an abundant number, since it is smaller than the sum of its proper divisors (854596300).

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

640704200 is a wasteful number, since it uses less digits than its factorization.

640704200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12194 (or 12185 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 640704200 is about 25312.1354294733. The cubic root of 640704200 is about 862.0898336797.

The spelling of 640704200 in words is "six hundred forty million, seven hundred four thousand, two hundred".