660999351600 has 720 divisors, whose sum is σ = 2811032939520. Its totient is φ = 140391014400.

The previous prime is 660999351569. The next prime is 660999351613. The reversal of 660999351600 is 6153999066.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (720).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 33833835 + ... + 33853365.

It is an arithmetic number, because the mean of its divisors is an integer number (3904212416).

Almost surely, 2^660999351600 is an apocalyptic number.

660999351600 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 660999351600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1405516469760).

660999351600 is an abundant number, since it is smaller than the sum of its proper divisors (2150033587920).

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

660999351600 is a wasteful number, since it uses less digits than its factorization.

660999351600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19658 (or 19644 counting only the distinct ones).

The product of its (nonzero) digits is 2361960, while the sum is 54.

The spelling of 660999351600 in words is "six hundred sixty billion, nine hundred ninety-nine million, three hundred fifty-one thousand, six hundred".