668933543520 has 576 divisors, whose sum is σ = 2581705840896. Its totient is φ = 156293591040.

The previous prime is 668933543497. The next prime is 668933543543. The reversal of 668933543520 is 25345339866.

668933543520 is a `hidden beast` number, since 6 + 6 + 8 + 93 + 3 + 543 + 5 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (668933543497) and next prime (668933543543).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 62705227 + ... + 62715893.

It is an arithmetic number, because the mean of its divisors is an integer number (4482128196).

Almost surely, 2^668933543520 is an apocalyptic number.

668933543520 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 668933543520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1290852920448).

668933543520 is an abundant number, since it is smaller than the sum of its proper divisors (1912772297376).

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

668933543520 is a wasteful number, since it uses less digits than its factorization.

668933543520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10843 (or 10832 counting only the distinct ones).

The product of its (nonzero) digits is 13996800, while the sum is 54.

The spelling of 668933543520 in words is "six hundred sixty-eight billion, nine hundred thirty-three million, five hundred forty-three thousand, five hundred twenty".