640550088 has 48 divisors (see below), whose sum is σ = 1754333100. Its totient is φ = 211115520.

The previous prime is 640550087. The next prime is 640550129. The reversal of 640550088 is 880055046.

It is a happy number.

640550088 is a `hidden beast` number, since 640 + 5 + 5 + 0 + 0 + 8 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 588450564 + 52099524 = 24258^2 + 7218^2 .

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

It is not an unprimeable number, because it can be changed into a prime (640550087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43573 + ... + 56388.

Almost surely, 2^640550088 is an apocalyptic number.

It is an amenable number.

640550088 is an abundant number, since it is smaller than the sum of its proper divisors (1113783012).

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

640550088 is a wasteful number, since it uses less digits than its factorization.

640550088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100062 (or 100055 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 36.

The square root of 640550088 is about 25309.0910148903. The cubic root of 640550088 is about 862.0207071143.

The spelling of 640550088 in words is "six hundred forty million, five hundred fifty thousand, eighty-eight".