640803 has 16 divisors (see below), whose sum is σ = 919296. Its totient is φ = 396000.

The previous prime is 640793. The next prime is 640837. The reversal of 640803 is 308046.

640803 is digitally balanced in base 2 and base 7, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640803 - 2⁵ = 640771 is a prime.

640803 is strictly pandigital in base 7.

It is a self number, because there is not a number n which added to its sum of digits gives 640803.

It is not an unprimeable number, because it can be changed into a prime (640853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2428 + ... + 2678.

It is an arithmetic number, because the mean of its divisors is an integer number (57456).

2⁶⁴⁰⁸⁰³ is an apocalyptic number.

640803 is a deficient number, since it is larger than the sum of its proper divisors (278493).

640803 is a wasteful number, since it uses less digits than its factorization.

640803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 640803 is about 800.5017176746. The cubic root of 640803 is about 86.2134144350.

Adding to 640803 its reverse (308046), we get a palindrome (948849).

The spelling of 640803 in words is "six hundred forty thousand, eight hundred three".