645242103 has 12 divisors (see below), whose sum is σ = 1016745288. Its totient is φ = 391055760.

The previous prime is 645242099. The next prime is 645242111. The reversal of 645242103 is 301242546.

645242103 is a `hidden beast` number, since 645 + 2 + 4 + 2 + 10 + 3 = 666.

It is not a de Polignac number, because 645242103 - 2² = 645242099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645242173) 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 11 ways as a sum of consecutive naturals, for example, 3258700 + ... + 3258897.

It is an arithmetic number, because the mean of its divisors is an integer number (84728774).

Almost surely, 2^645242103 is an apocalyptic number.

645242103 is a deficient number, since it is larger than the sum of its proper divisors (371503185).

645242103 is a wasteful number, since it uses less digits than its factorization.

645242103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6517614 (or 6517611 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 645242103 is about 25401.6161493713. The cubic root of 645242103 is about 864.1203495869.

Adding to 645242103 its reverse (301242546), we get a palindrome (946484649).

The spelling of 645242103 in words is "six hundred forty-five million, two hundred forty-two thousand, one hundred three".