640860480720 has 160 divisors (see below), whose sum is σ = 2243595805440. Its totient is φ = 168094517760.

The previous prime is 640860480697. The next prime is 640860480727. The reversal of 640860480720 is 27084068046.

640860480720 is a `hidden beast` number, since 6 + 40 + 8 + 60 + 480 + 72 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640860480727) 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 31 ways as a sum of consecutive naturals, for example, 2300164 + ... + 2563683.

It is an arithmetic number, because the mean of its divisors is an integer number (14022473784).

Almost surely, 2^640860480720 is an apocalyptic number.

640860480720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

640860480720 is an abundant number, since it is smaller than the sum of its proper divisors (1602735324720).

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

640860480720 is a wasteful number, since it uses less digits than its factorization.

640860480720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4863930 (or 4863918 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 45.

The spelling of 640860480720 in words is "six hundred forty billion, eight hundred sixty million, four hundred eighty thousand, seven hundred twenty".