645264044 has 24 divisors (see below), whose sum is σ = 1139025888. Its totient is φ = 319840640.

The previous prime is 645264017. The next prime is 645264083. The reversal of 645264044 is 440462546.

It is a junction number, because it is equal to n+sod(n) for n = 645263995 and 645264013.

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 7 ways as a sum of consecutive naturals, for example, 243752 + ... + 246384.

It is an arithmetic number, because the mean of its divisors is an integer number (47459412).

Almost surely, 2^645264044 is an apocalyptic number.

It is an amenable number.

645264044 is a deficient number, since it is larger than the sum of its proper divisors (493761844).

645264044 is a wasteful number, since it uses less digits than its factorization.

645264044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3145 (or 3143 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 35.

The square root of 645264044 is about 25402.0480276690. The cubic root of 645264044 is about 864.1301440757.

The spelling of 645264044 in words is "six hundred forty-five million, two hundred sixty-four thousand, forty-four".