645507445 has 16 divisors (see below), whose sum is σ = 846744192. Its totient is φ = 468506560.

The previous prime is 645507427. The next prime is 645507469. The reversal of 645507445 is 544705546.

It is a happy number.

It is not a de Polignac number, because 645507445 - 2⁹ = 645506933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645507398 and 645507407.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 15999 + ... + 39331.

It is an arithmetic number, because the mean of its divisors is an integer number (52921512).

Almost surely, 2^645507445 is an apocalyptic number.

It is an amenable number.

645507445 is a deficient number, since it is larger than the sum of its proper divisors (201236747).

645507445 is a wasteful number, since it uses less digits than its factorization.

645507445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23852.

The product of its (nonzero) digits is 336000, while the sum is 40.

The square root of 645507445 is about 25406.8385479186. The cubic root of 645507445 is about 864.2387836848.

The spelling of 645507445 in words is "six hundred forty-five million, five hundred seven thousand, four hundred forty-five".