640088 has 32 divisors (see below), whose sum is σ = 1296000. Its totient is φ = 295680.

The previous prime is 640069. The next prime is 640099. The reversal of 640088 is 880046.

640088 is a modest number, since divided by 88 gives 64 as remainder.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 640088.

It is an unprimeable number.

640088 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7148 + ... + 7236.

It is an arithmetic number, because the mean of its divisors is an integer number (40500).

2⁶⁴⁰⁰⁸⁸ is an apocalyptic number.

It is an amenable number.

640088 is an abundant number, since it is smaller than the sum of its proper divisors (655912).

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

640088 is a wasteful number, since it uses less digits than its factorization.

640088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 640088 is about 800.0549981095. The cubic root of 640088 is about 86.1813372172.

The spelling of 640088 in words is "six hundred forty thousand, eighty-eight".