645413280 has 96 divisors (see below), whose sum is σ = 2140084800. Its totient is φ = 163049472.

The previous prime is 645413243. The next prime is 645413287. The reversal of 645413280 is 82314546.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (645413287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26265 + ... + 44504.

It is an arithmetic number, because the mean of its divisors is an integer number (22292550).

Almost surely, 2^645413280 is an apocalyptic number.

645413280 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

645413280 is an abundant number, since it is smaller than the sum of its proper divisors (1494671520).

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

645413280 is a wasteful number, since it uses less digits than its factorization.

645413280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70806 (or 70798 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The square root of 645413280 is about 25404.9853375278. The cubic root of 645413280 is about 864.1967573156.

The spelling of 645413280 in words is "six hundred forty-five million, four hundred thirteen thousand, two hundred eighty".