665168088400 has 30 divisors (see below), whose sum is σ = 1598066333342. Its totient is φ = 266067235200.

The previous prime is 665168088397. The next prime is 665168088413. The reversal of 665168088400 is 4880861566.

It can be written as a sum of positive squares in 3 ways, for example, as 2585112336 + 662582976064 = 50844^2 + 813992^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 831459711 + ... + 831460510.

Almost surely, 2^665168088400 is an apocalyptic number.

It is an amenable number.

665168088400 is an abundant number, since it is smaller than the sum of its proper divisors (932898244942).

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

665168088400 is a wasteful number, since it uses less digits than its factorization.

665168088400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1662920239 (or 1662920228 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 52.

The spelling of 665168088400 in words is "six hundred sixty-five billion, one hundred sixty-eight million, eighty-eight thousand, four hundred".