640930 has 16 divisors (see below), whose sum is σ = 1166400. Its totient is φ = 253552.

The previous prime is 640919. The next prime is 640933. The reversal of 640930 is 39046.

640930 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (640933) 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, 771 + ... + 1369.

It is an arithmetic number, because the mean of its divisors is an integer number (72900).

2⁶⁴⁰⁹³⁰ is an apocalyptic number.

640930 is a deficient number, since it is larger than the sum of its proper divisors (525470).

640930 is a wasteful number, since it uses less digits than its factorization.

640930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 640930 is about 800.5810389961. The cubic root of 640930 is about 86.2191095708.

Adding to 640930 its reverse (39046), we get a palindrome (679976).

The spelling of 640930 in words is "six hundred forty thousand, nine hundred thirty".