663991896960 has 1536 divisors, whose sum is σ = 2924562931200. Its totient is φ = 141463977984.

The previous prime is 663991896937. The next prime is 663991896973. The reversal of 663991896960 is 69698199366.

663991896960 is a `hidden beast` number, since 66 + 399 + 1 + 8 + 96 + 96 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

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 191 ways as a sum of consecutive naturals, for example, 2346260979 + ... + 2346261261.

It is an arithmetic number, because the mean of its divisors is an integer number (1904012325).

Almost surely, 2^663991896960 is an apocalyptic number.

663991896960 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 663991896960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1462281465600).

663991896960 is an abundant number, since it is smaller than the sum of its proper divisors (2260571034240).

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

663991896960 is a wasteful number, since it uses less digits than its factorization.

663991896960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505 (or 480 counting only the distinct ones).

The product of its (nonzero) digits is 204073344, while the sum is 72.

The spelling of 663991896960 in words is "six hundred sixty-three billion, nine hundred ninety-one million, eight hundred ninety-six thousand, nine hundred sixty".