640424880 has 200 divisors, whose sum is σ = 2321538912. Its totient is φ = 163316736.

The previous prime is 640424861. The next prime is 640424891. The reversal of 640424880 is 88424046.

640424880 is a `hidden beast` number, since 6 + 404 + 248 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 39 ways as a sum of consecutive naturals, for example, 146892 + ... + 151188.

Almost surely, 2^640424880 is an apocalyptic number.

640424880 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 640424880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1160769456).

640424880 is an abundant number, since it is smaller than the sum of its proper divisors (1681114032).

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

640424880 is a wasteful number, since it uses less digits than its factorization.

640424880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4345 (or 4330 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 36.

The square root of 640424880 is about 25306.6173164254. The cubic root of 640424880 is about 861.9645372046.

The spelling of 640424880 in words is "six hundred forty million, four hundred twenty-four thousand, eight hundred eighty".