640414566 has 64 divisors (see below), whose sum is σ = 1588688640. Its totient is φ = 189544320.

The previous prime is 640414559. The next prime is 640414597. The reversal of 640414566 is 665414046.

640414566 is a `hidden beast` number, since 640 + 4 + 1 + 4 + 5 + 6 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 640414566.

It is a congruent number.

It is an unprimeable number.

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, 13006 + ... + 38078.

It is an arithmetic number, because the mean of its divisors is an integer number (24823260).

Almost surely, 2^640414566 is an apocalyptic number.

640414566 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 640414566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (794344320).

640414566 is an abundant number, since it is smaller than the sum of its proper divisors (948274074).

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

640414566 is a wasteful number, since it uses less digits than its factorization.

640414566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25138 (or 25132 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 640414566 is about 25306.4135349124. The cubic root of 640414566 is about 861.9599098859.

The spelling of 640414566 in words is "six hundred forty million, four hundred fourteen thousand, five hundred sixty-six".