640348560 has 60 divisors (see below), whose sum is σ = 2150506332. Its totient is φ = 170759424.

The previous prime is 640348531. The next prime is 640348649. The reversal of 640348560 is 65843046.

640348560 is a `hidden beast` number, since 64 + 0 + 34 + 8 + 560 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 150700176 + 489648384 = 12276^2 + 22128^2 .

It is a tau number, because it is divible by the number of its divisors (60).

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 11 ways as a sum of consecutive naturals, for example, 443967 + ... + 445406.

Almost surely, 2^640348560 is an apocalyptic number.

640348560 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

640348560 is an abundant number, since it is smaller than the sum of its proper divisors (1510157772).

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

640348560 is a wasteful number, since it uses less digits than its factorization.

640348560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 889392 (or 889383 counting only the distinct ones).

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

The square root of 640348560 is about 25305.1093655017. The cubic root of 640348560 is about 861.9302954853.

The spelling of 640348560 in words is "six hundred forty million, three hundred forty-eight thousand, five hundred sixty".