640612 has 24 divisors (see below), whose sum is σ = 1298304. Its totient is φ = 270912.

The previous prime is 640589. The next prime is 640613. The reversal of 640612 is 216046.

It is a self number, because there is not a number n which added to its sum of digits gives 640612.

It is not an unprimeable number, because it can be changed into a prime (640613) 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, 3753 + ... + 3919.

It is an arithmetic number, because the mean of its divisors is an integer number (54096).

2⁶⁴⁰⁶¹² is an apocalyptic number.

It is an amenable number.

640612 is an abundant number, since it is smaller than the sum of its proper divisors (657692).

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

640612 is a wasteful number, since it uses less digits than its factorization.

640612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315 (or 313 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 640612 is about 800.3824086023. The cubic root of 640612 is about 86.2048478925.

Adding to 640612 its reverse (216046), we get a palindrome (856658).

The spelling of 640612 in words is "six hundred forty thousand, six hundred twelve".