640063 has 4 divisors (see below), whose sum is σ = 657400. Its totient is φ = 622728.

The previous prime is 640061. The next prime is 640069. The reversal of 640063 is 360046.

640063 = T₄₇ + T₄₈ + ... + T₁₅₇.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 360046 = 2 ⋅180023.

It is a cyclic number.

It is not a de Polignac number, because 640063 - 2¹ = 640061 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 640063.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8613 + ... + 8686.

It is an arithmetic number, because the mean of its divisors is an integer number (164350).

2⁶⁴⁰⁰⁶³ is an apocalyptic number.

640063 is a deficient number, since it is larger than the sum of its proper divisors (17337).

640063 is a wasteful number, since it uses less digits than its factorization.

640063 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17336.

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 640063 is about 800.0393740311. The cubic root of 640063 is about 86.1802152040.

It can be divided in two parts, 64006 and 3, that added together give a square (64009 = 253²).

The spelling of 640063 in words is "six hundred forty thousand, sixty-three".