645543360 has 672 divisors, whose sum is σ = 2875751424. Its totient is φ = 129024000.

The previous prime is 645543347. The next prime is 645543361. The reversal of 645543360 is 63345546.

645543360 is a `hidden beast` number, since 645 + 5 + 4 + 3 + 3 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645543361) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 9092125 + ... + 9092195.

It is an arithmetic number, because the mean of its divisors is an integer number (4279392).

Almost surely, 2^645543360 is an apocalyptic number.

645543360 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 645543360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1437875712).

645543360 is an abundant number, since it is smaller than the sum of its proper divisors (2230208064).

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

645543360 is a wasteful number, since it uses less digits than its factorization.

645543360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153 (or 140 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 36.

The square root of 645543360 is about 25407.5453359824. The cubic root of 645543360 is about 864.2548116746.

The spelling of 645543360 in words is "six hundred forty-five million, five hundred forty-three thousand, three hundred sixty".