645907584 has 128 divisors (see below), whose sum is σ = 2064153600. Its totient is φ = 174818304.

The previous prime is 645907583. The next prime is 645907607. The reversal of 645907584 is 485709546.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (645907583) 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, 44749 + ... + 57395.

It is an arithmetic number, because the mean of its divisors is an integer number (16126200).

Almost surely, 2^645907584 is an apocalyptic number.

645907584 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645907584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1032076800).

645907584 is an abundant number, since it is smaller than the sum of its proper divisors (1418246016).

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

645907584 is a wasteful number, since it uses less digits than its factorization.

645907584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12690 (or 12678 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 48.

The square root of 645907584 is about 25414.7119598078. The cubic root of 645907584 is about 864.4173224013.

The spelling of 645907584 in words is "six hundred forty-five million, nine hundred seven thousand, five hundred eighty-four".