665450880 has 64 divisors (see below), whose sum is σ = 2121130800. Its totient is φ = 177453056.

The previous prime is 665450879. The next prime is 665450921. The reversal of 665450880 is 88054566.

665450880 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 171375 + ... + 175214.

Almost surely, 2^665450880 is an apocalyptic number.

665450880 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

665450880 is an abundant number, since it is smaller than the sum of its proper divisors (1455679920).

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

665450880 is a wasteful number, since it uses less digits than its factorization.

665450880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346611 (or 346599 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 42.

The square root of 665450880 is about 25796.3346233530. The cubic root of 665450880 is about 873.0490978502.

The spelling of 665450880 in words is "six hundred sixty-five million, four hundred fifty thousand, eight hundred eighty".