643722266880000 has 3600 divisors, whose sum is σ = 3049291134489600. Its totient is φ = 133748858880000.

The previous prime is 643722266879971. The next prime is 643722266880013. The reversal of 643722266880000 is 88662227346.

643722266880000 is a `hidden beast` number, since 6 + 4 + 372 + 2 + 266 + 8 + 8 + 0 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (3600).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 299 ways as a sum of consecutive naturals, for example, 55883514241 + ... + 55883525759.

It is an arithmetic number, because the mean of its divisors is an integer number (847025315136).

Almost surely, 2^{643722266880000} is an apocalyptic number.

643722266880000 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 643722266880000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1524645567244800).

643722266880000 is an abundant number, since it is smaller than the sum of its proper divisors (2405568867609600).

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

643722266880000 is a wasteful number, since it uses less digits than its factorization.

643722266880000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11598 (or 11547 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 54.

The spelling of 643722266880000 in words is "six hundred forty-three trillion, seven hundred twenty-two billion, two hundred sixty-six million, eight hundred eighty thousand".