645140064 has 48 divisors (see below), whose sum is σ = 1767128832. Its totient is φ = 205696128.

The previous prime is 645140059. The next prime is 645140071. The reversal of 645140064 is 460041546.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 143884 + ... + 148299.

It is an arithmetic number, because the mean of its divisors is an integer number (36815184).

Almost surely, 2^645140064 is an apocalyptic number.

It is an amenable number.

645140064 is an abundant number, since it is smaller than the sum of its proper divisors (1121988768).

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

645140064 is a wasteful number, since it uses less digits than its factorization.

645140064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292219 (or 292211 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 645140064 is about 25399.6075560234. The cubic root of 645140064 is about 864.0747963368.

The spelling of 645140064 in words is "six hundred forty-five million, one hundred forty thousand, sixty-four".