663968894400 has 1512 divisors, whose sum is σ = 2893605047424. Its totient is φ = 143700480000.

The previous prime is 663968894341. The next prime is 663968894489. The reversal of 663968894400 is 4498869366.

663968894400 is a `hidden beast` number, since 6 + 63 + 9 + 6 + 88 + 94 + 400 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 2645294275 + ... + 2645294525.

It is an arithmetic number, because the mean of its divisors is an integer number (1913759952).

Almost surely, 2^663968894400 is an apocalyptic number.

663968894400 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 663968894400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1446802523712).

663968894400 is an abundant number, since it is smaller than the sum of its proper divisors (2229636153024).

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

663968894400 is a wasteful number, since it uses less digits than its factorization.

663968894400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 479 (or 454 counting only the distinct ones).

The product of its (nonzero) digits is 53747712, while the sum is 63.

The spelling of 663968894400 in words is "six hundred sixty-three billion, nine hundred sixty-eight million, eight hundred ninety-four thousand, four hundred".