640120320000 has 1820 divisors, whose sum is σ = 2796843161200. Its totient is φ = 146313216000.

The previous prime is 640120319987. The next prime is 640120320043. The reversal of 640120320000 is 23021046.

It is a happy number.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

640120320000 is a `hidden beast` number, since 640 + 1 + 2 + 0 + 3 + 20 + 0 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 139 ways as a sum of consecutive naturals, for example, 91445759997 + ... + 91445760003.

Almost surely, 2^640120320000 is an apocalyptic number.

640120320000 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640120320000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1398421580600).

640120320000 is an abundant number, since it is smaller than the sum of its proper divisors (2156722841200).

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

640120320000 is an frugal number, since it uses more digits than its factorization.

640120320000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 640120320000 its reverse (23021046), we get a palindrome (640143341046).

The spelling of 640120320000 in words is "six hundred forty billion, one hundred twenty million, three hundred twenty thousand".