645560032 has 96 divisors (see below), whose sum is σ = 1415715840. Its totient is φ = 287884800.

The previous prime is 645559991. The next prime is 645560143. The reversal of 645560032 is 230065546.

It is a junction number, because it is equal to n+sod(n) for n = 645559976 and 645560003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2700969 + ... + 2701207.

It is an arithmetic number, because the mean of its divisors is an integer number (14747040).

Almost surely, 2^645560032 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645560032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (707857920).

645560032 is an abundant number, since it is smaller than the sum of its proper divisors (770155808).

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

645560032 is a wasteful number, since it uses less digits than its factorization.

645560032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 31.

The square root of 645560032 is about 25407.8734253774. The cubic root of 645560032 is about 864.2622517801.

The spelling of 645560032 in words is "six hundred forty-five million, five hundred sixty thousand, thirty-two".