645813064 has 32 divisors (see below), whose sum is σ = 1349019000. Its totient is φ = 287788032.

The previous prime is 645813061. The next prime is 645813073. The reversal of 645813064 is 460318546.

It is a happy number.

645813064 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 247810564 + 398002500 = 15742^2 + 19950^2 .

It is not an unprimeable number, because it can be changed into a prime (645813061) 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, 104049 + ... + 110080.

Almost surely, 2^645813064 is an apocalyptic number.

It is an amenable number.

645813064 is an abundant number, since it is smaller than the sum of its proper divisors (703205936).

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

645813064 is a wasteful number, since it uses less digits than its factorization.

645813064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214177 (or 214173 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 645813064 is about 25412.8523389249. The cubic root of 645813064 is about 864.3751550112.

The spelling of 645813064 in words is "six hundred forty-five million, eight hundred thirteen thousand, sixty-four".