645033440 has 48 divisors (see below), whose sum is σ = 1526545440. Its totient is φ = 257564160.

The previous prime is 645033427. The next prime is 645033449. The reversal of 645033440 is 44330546.

645033440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645033449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97766 + ... + 104154.

It is an arithmetic number, because the mean of its divisors is an integer number (31803030).

Almost surely, 2^645033440 is an apocalyptic number.

It is an amenable number.

645033440 is an abundant number, since it is smaller than the sum of its proper divisors (881512000).

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

645033440 is a wasteful number, since it uses less digits than its factorization.

645033440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7035 (or 7027 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 29.

The square root of 645033440 is about 25397.5085392249. The cubic root of 645033440 is about 864.0271910738.

Adding to 645033440 its reverse (44330546), we get a palindrome (689363986).

The spelling of 645033440 in words is "six hundred forty-five million, thirty-three thousand, four hundred forty".