643840404480 has 1056 divisors, whose sum is σ = 2798482587264. Its totient is φ = 133234163712.

The previous prime is 643840404457. The next prime is 643840404497. The reversal of 643840404480 is 84404048346.

643840404480 is a `hidden beast` number, since 64 + 38 + 40 + 40 + 4 + 480 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 222242392 + ... + 222245288.

Almost surely, 2^643840404480 is an apocalyptic number.

643840404480 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 643840404480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1399241293632).

643840404480 is an abundant number, since it is smaller than the sum of its proper divisors (2154642182784).

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

643840404480 is a wasteful number, since it uses less digits than its factorization.

643840404480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3001 (or 2980 counting only the distinct ones).

The product of its (nonzero) digits is 1179648, while the sum is 45.

The spelling of 643840404480 in words is "six hundred forty-three billion, eight hundred forty million, four hundred four thousand, four hundred eighty".