645739108 has 48 divisors (see below), whose sum is σ = 1311932160. Its totient is φ = 272398464.

The previous prime is 645739091. The next prime is 645739109. The reversal of 645739108 is 801937546.

645739108 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (645739109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 527385 + ... + 528607.

It is an arithmetic number, because the mean of its divisors is an integer number (27331920).

Almost surely, 2^645739108 is an apocalyptic number.

It is an amenable number.

645739108 is an abundant number, since it is smaller than the sum of its proper divisors (666193052).

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

645739108 is a wasteful number, since it uses less digits than its factorization.

645739108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1516 (or 1514 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 43.

The square root of 645739108 is about 25411.3972067653. The cubic root of 645739108 is about 864.3421587915.

The spelling of 645739108 in words is "six hundred forty-five million, seven hundred thirty-nine thousand, one hundred eight".