640587 has 8 divisors (see below), whose sum is σ = 867136. Its totient is φ = 420552.

The previous prime is 640583. The next prime is 640589. The reversal of 640587 is 785046.

It is a happy number.

640587 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640587 - 2² = 640583 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 640587.

It is not an unprimeable number, because it can be changed into a prime (640583) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1393 + ... + 1794.

It is an arithmetic number, because the mean of its divisors is an integer number (108392).

2⁶⁴⁰⁵⁸⁷ is an apocalyptic number.

640587 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

640587 is a deficient number, since it is larger than the sum of its proper divisors (226549).

640587 is a wasteful number, since it uses less digits than its factorization.

640587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3257.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 640587 is about 800.3667909153. The cubic root of 640587 is about 86.2037264912.

The spelling of 640587 in words is "six hundred forty thousand, five hundred eighty-seven".