665545507200 has 1344 divisors, whose sum is σ = 2874064485600. Its totient is φ = 149060321280.

The previous prime is 665545507153. The next prime is 665545507213. The reversal of 665545507200 is 2705545566.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 167 ways as a sum of consecutive naturals, for example, 865468416 + ... + 865469184.

Almost surely, 2^665545507200 is an apocalyptic number.

665545507200 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 665545507200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1437032242800).

665545507200 is an abundant number, since it is smaller than the sum of its proper divisors (2208518978400).

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

665545507200 is an equidigital number, since it uses as much as digits as its factorization.

665545507200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 871 (or 839 counting only the distinct ones).

The product of its (nonzero) digits is 1260000, while the sum is 45.

The spelling of 665545507200 in words is "six hundred sixty-five billion, five hundred forty-five million, five hundred seven thousand, two hundred".