643003 has 4 divisors (see below), whose sum is σ = 658728. Its totient is φ = 627280.

The previous prime is 642997. The next prime is 643009. The reversal of 643003 is 300346.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (642997) and next prime (643009).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7801 + ... + 7882.

It is an arithmetic number, because the mean of its divisors is an integer number (164682).

2⁶⁴³⁰⁰³ is an apocalyptic number.

643003 is a deficient number, since it is larger than the sum of its proper divisors (15725).

643003 is a wasteful number, since it uses less digits than its factorization.

643003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15724.

The product of its (nonzero) digits is 216, while the sum is 16.

The square root of 643003 is about 801.8746784879. The cubic root of 643003 is about 86.3119641544.

Adding to 643003 its reverse (300346), we get a palindrome (943349).

The spelling of 643003 in words is "six hundred forty-three thousand, three".