645308945 has 8 divisors (see below), whose sum is σ = 776482944. Its totient is φ = 514839024.

The previous prime is 645308941. The next prime is 645309043. The reversal of 645308945 is 549803546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645308945 - 2² = 645308941 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645308896 and 645308905.

It is not an unprimeable number, because it can be changed into a prime (645308941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173999 + ... + 177668.

It is an arithmetic number, because the mean of its divisors is an integer number (97060368).

Almost surely, 2^645308945 is an apocalyptic number.

It is an amenable number.

645308945 is a deficient number, since it is larger than the sum of its proper divisors (131173999).

645308945 is a wasteful number, since it uses less digits than its factorization.

645308945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352039.

The product of its (nonzero) digits is 518400, while the sum is 44.

The square root of 645308945 is about 25402.9318189850. The cubic root of 645308945 is about 864.1501872441.

The spelling of 645308945 in words is "six hundred forty-five million, three hundred eight thousand, nine hundred forty-five".