643442021913600 has 12672 divisors, whose sum is σ = 3435192000307200. Its totient is φ = 115785471098880.

The previous prime is 643442021913557. The next prime is 643442021913629. The reversal of 643442021913600 is 6319120244346.

643442021913600 is a `hidden beast` number, since 6 + 4 + 3 + 4 + 4 + 2 + 0 + 21 + 9 + 13 + 600 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 1151 ways as a sum of consecutive naturals, for example, 27975740083189 + ... + 27975740083211.

Almost surely, 2^{643442021913600} is an apocalyptic number.

643442021913600 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 643442021913600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1717596000153600).

643442021913600 is an abundant number, since it is smaller than the sum of its proper divisors (2791749978393600).

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

643442021913600 is a wasteful number, since it uses less digits than its factorization.

643442021913600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 45.

The spelling of 643442021913600 in words is "six hundred forty-three trillion, four hundred forty-two billion, twenty-one million, nine hundred thirteen thousand, six hundred".