640333 has 2 divisors, whose sum is σ = 640334. Its totient is φ = 640332.

The previous prime is 640307. The next prime is 640363. The reversal of 640333 is 333046.

It is a happy number.

640333 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 407044 + 233289 = 638^2 + 483^2 .

It is a cyclic number.

It is not a de Polignac number, because 640333 - 2¹³ = 632141 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 640333.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320166 + 320167.

It is an arithmetic number, because the mean of its divisors is an integer number (320167).

2⁶⁴⁰³³³ is an apocalyptic number.

It is an amenable number.

640333 is a deficient number, since it is larger than the sum of its proper divisors (1).

640333 is an equidigital number, since it uses as much as digits as its factorization.

640333 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 19.

The square root of 640333 is about 800.2080979345. The cubic root of 640333 is about 86.1923314004.

Adding to 640333 its reverse (333046), we get a palindrome (973379).

The spelling of 640333 in words is "six hundred forty thousand, three hundred thirty-three".