645003543 has 4 divisors (see below), whose sum is σ = 860004728. Its totient is φ = 430002360.

The previous prime is 645003539. The next prime is 645003553. The reversal of 645003543 is 345300546.

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

It is not a de Polignac number, because 645003543 - 2² = 645003539 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 645003543.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645003553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107500588 + ... + 107500593.

It is an arithmetic number, because the mean of its divisors is an integer number (215001182).

Almost surely, 2^645003543 is an apocalyptic number.

645003543 is a deficient number, since it is larger than the sum of its proper divisors (215001185).

645003543 is a wasteful number, since it uses less digits than its factorization.

645003543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215001184.

The product of its (nonzero) digits is 21600, while the sum is 30.

The square root of 645003543 is about 25396.9199510492. The cubic root of 645003543 is about 864.0138417814.

It can be divided in two parts, 645003 and 543, that added together give a palindrome (645546).

The spelling of 645003543 in words is "six hundred forty-five million, three thousand, five hundred forty-three".