640258560 has 320 divisors, whose sum is σ = 2327529600. Its totient is φ = 166772736.

The previous prime is 640258547. The next prime is 640258579. The reversal of 640258560 is 65852046.

640258560 is a `hidden beast` number, since 6 + 40 + 2 + 58 + 560 = 666.

It is a tau number, because it is divible by the number of its divisors (320).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4078002 + ... + 4078158.

It is an arithmetic number, because the mean of its divisors is an integer number (7273530).

Almost surely, 2^640258560 is an apocalyptic number.

640258560 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 640258560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1163764800).

640258560 is an abundant number, since it is smaller than the sum of its proper divisors (1687271040).

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

640258560 is a wasteful number, since it uses less digits than its factorization.

640258560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248 (or 226 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 640258560 is about 25303.3310060158. The cubic root of 640258560 is about 861.8899126032.

The spelling of 640258560 in words is "six hundred forty million, two hundred fifty-eight thousand, five hundred sixty".