645322500 has 360 divisors, whose sum is σ = 2251529280. Its totient is φ = 155232000.

The previous prime is 645322453. The next prime is 645322511. The reversal of 645322500 is 5223546.

645322500 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×645322500² = 832882258012500000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 15007479 + ... + 15007521.

It is an arithmetic number, because the mean of its divisors is an integer number (6254248).

Almost surely, 2^645322500 is an apocalyptic number.

645322500 is a gapful number since it is divisible by the number (60) 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 645322500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1125764640).

645322500 is an abundant number, since it is smaller than the sum of its proper divisors (1606206780).

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

645322500 is a wasteful number, since it uses less digits than its factorization.

645322500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The square root of 645322500 is about 25403.1986174970. The cubic root of 645322500 is about 864.1562378208.

The spelling of 645322500 in words is "six hundred forty-five million, three hundred twenty-two thousand, five hundred".