645442303 has 4 divisors (see below), whose sum is σ = 704118888. Its totient is φ = 586765720.

The previous prime is 645442277. The next prime is 645442309. The reversal of 645442303 is 303244546.

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

It is a cyclic number.

It is not a de Polignac number, because 645442303 - 2⁵ = 645442271 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645442309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29338276 + ... + 29338297.

It is an arithmetic number, because the mean of its divisors is an integer number (176029722).

Almost surely, 2^645442303 is an apocalyptic number.

645442303 is a deficient number, since it is larger than the sum of its proper divisors (58676585).

645442303 is a wasteful number, since it uses less digits than its factorization.

645442303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58676584.

The product of its (nonzero) digits is 34560, while the sum is 31.

The square root of 645442303 is about 25405.5565378915. The cubic root of 645442303 is about 864.2097108795.

Adding to 645442303 its reverse (303244546), we get a palindrome (948686849).

The spelling of 645442303 in words is "six hundred forty-five million, four hundred forty-two thousand, three hundred three".