665416980 has 36 divisors (see below), whose sum is σ = 2018432052. Its totient is φ = 177444480.

The previous prime is 665416967. The next prime is 665417033. The reversal of 665416980 is 89614566.

665416980 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 208398096 + 457018884 = 14436^2 + 21378^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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 polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1848201 + ... + 1848560.

It is an arithmetic number, because the mean of its divisors is an integer number (56067557).

Almost surely, 2^665416980 is an apocalyptic number.

665416980 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

665416980 is an abundant number, since it is smaller than the sum of its proper divisors (1353015072).

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

665416980 is a wasteful number, since it uses less digits than its factorization.

665416980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3696776 (or 3696771 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 665416980 is about 25795.6775448911. The cubic root of 665416980 is about 873.0342723798.

The spelling of 665416980 in words is "six hundred sixty-five million, four hundred sixteen thousand, nine hundred eighty".