640950 has 24 divisors (see below), whose sum is σ = 1589928. Its totient is φ = 170880.

The previous prime is 640949. The next prime is 640957. The reversal of 640950 is 59046.

It is a self number, because there is not a number n which added to its sum of digits gives 640950.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640957) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1987 + ... + 2286.

It is an arithmetic number, because the mean of its divisors is an integer number (66247).

2⁶⁴⁰⁹⁵⁰ is an apocalyptic number.

640950 is an abundant number, since it is smaller than the sum of its proper divisors (948978).

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

640950 is a wasteful number, since it uses less digits than its factorization.

640950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4288 (or 4283 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 640950 is about 800.5935298265. The cubic root of 640950 is about 86.2200063741.

Adding to 640950 its reverse (59046), we get a palindrome (699996).

The spelling of 640950 in words is "six hundred forty thousand, nine hundred fifty".