645240500 has 48 divisors (see below), whose sum is σ = 1420106688. Its totient is φ = 256100000.

The previous prime is 645240481. The next prime is 645240511. The reversal of 645240500 is 5042546.

It is a self number, because there is not a number n which added to its sum of digits gives 645240500.

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, 60575 + ... + 70425.

It is an arithmetic number, because the mean of its divisors is an integer number (29585556).

Almost surely, 2^645240500 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 645240500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (710053344).

645240500 is an abundant number, since it is smaller than the sum of its proper divisors (774866188).

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

645240500 is a wasteful number, since it uses less digits than its factorization.

645240500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10001 (or 9989 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 645240500 is about 25401.5845962412. The cubic root of 645240500 is about 864.1196339971.

The spelling of 645240500 in words is "six hundred forty-five million, two hundred forty thousand, five hundred".