665146823720 has 16 divisors (see below), whose sum is σ = 1496580353460. Its totient is φ = 266058729472.

The previous prime is 665146823717. The next prime is 665146823813. The reversal of 665146823720 is 27328641566.

It is a happy number.

665146823720 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 613800170116 + 51346653604 = 783454^2 + 226598^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8314335257 + ... + 8314335336.

Almost surely, 2^665146823720 is an apocalyptic number.

It is an amenable number.

665146823720 is an abundant number, since it is smaller than the sum of its proper divisors (831433529740).

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

665146823720 is a wasteful number, since it uses less digits than its factorization.

665146823720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16628670604 (or 16628670600 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 50.

The spelling of 665146823720 in words is "six hundred sixty-five billion, one hundred forty-six million, eight hundred twenty-three thousand, seven hundred twenty".