643455360 has 256 divisors, whose sum is σ = 2379456000. Its totient is φ = 164026368.

The previous prime is 643455359. The next prime is 643455391. The reversal of 643455360 is 63554346.

643455360 is a `hidden beast` number, since 6 + 43 + 4 + 553 + 60 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 396631 + ... + 398249.

It is an arithmetic number, because the mean of its divisors is an integer number (9294750).

Almost surely, 2^643455360 is an apocalyptic number.

643455360 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 643455360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1189728000).

643455360 is an abundant number, since it is smaller than the sum of its proper divisors (1736000640).

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

643455360 is a wasteful number, since it uses less digits than its factorization.

643455360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1670 (or 1652 counting only the distinct ones).

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

The square root of 643455360 is about 25366.4218998266. The cubic root of 643455360 is about 863.3219989601.

The spelling of 643455360 in words is "six hundred forty-three million, four hundred fifty-five thousand, three hundred sixty".