645376800 has 144 divisors (see below), whose sum is σ = 2211420960. Its totient is φ = 163031040.

The previous prime is 645376799. The next prime is 645376801. The reversal of 645376800 is 8673546.

645376800 is digitally balanced in base 2 and base 6, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (645376799) and next prime (645376801).

It is a super-2 number, since 2×645376800² = 833022427956480000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645376801) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38524 + ... + 52676.

It is an arithmetic number, because the mean of its divisors is an integer number (15357090).

Almost surely, 2^645376800 is an apocalyptic number.

645376800 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 645376800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1105710480).

645376800 is an abundant number, since it is smaller than the sum of its proper divisors (1566044160).

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

645376800 is a wasteful number, since it uses less digits than its factorization.

645376800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14195 (or 14182 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 39.

The square root of 645376800 is about 25404.2673580641. The cubic root of 645376800 is about 864.1804749878.

The spelling of 645376800 in words is "six hundred forty-five million, three hundred seventy-six thousand, eight hundred".