646401484800 has 864 divisors, whose sum is σ = 2456257789440. Its totient is φ = 162172108800.

The previous prime is 646401484747. The next prime is 646401484811. The reversal of 646401484800 is 8484104646.

646401484800 is a `hidden beast` number, since 6 + 464 + 0 + 148 + 48 + 0 + 0 = 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 pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 528536989 + ... + 528538211.

It is an arithmetic number, because the mean of its divisors is an integer number (2842890960).

Almost surely, 2^646401484800 is an apocalyptic number.

646401484800 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 646401484800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1228128894720).

646401484800 is an abundant number, since it is smaller than the sum of its proper divisors (1809856304640).

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

646401484800 is a wasteful number, since it uses less digits than its factorization.

646401484800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1329 (or 1301 counting only the distinct ones).

The product of its (nonzero) digits is 589824, while the sum is 45.

The spelling of 646401484800 in words is "six hundred forty-six billion, four hundred one million, four hundred eighty-four thousand, eight hundred".