645418938 has 16 divisors (see below), whose sum is σ = 1291332960. Its totient is φ = 215057136.

The previous prime is 645418937. The next prime is 645418997. The reversal of 645418938 is 839814546.

It is not an unprimeable number, because it can be changed into a prime (645418933) by changing a digit.

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, 2448 + ... + 36011.

It is an arithmetic number, because the mean of its divisors is an integer number (80708310).

Almost surely, 2^645418938 is an apocalyptic number.

645418938 is an abundant number, since it is smaller than the sum of its proper divisors (645914022).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645418938 is a wasteful number, since it uses less digits than its factorization.

645418938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41261.

The product of its digits is 829440, while the sum is 48.

The square root of 645418938 is about 25405.0966933802. The cubic root of 645418938 is about 864.1992826282.

The spelling of 645418938 in words is "six hundred forty-five million, four hundred eighteen thousand, nine hundred thirty-eight".