665745128 has 16 divisors (see below), whose sum is σ = 1248712260. Its totient is φ = 332755200.

The previous prime is 665745029. The next prime is 665745133. The reversal of 665745128 is 821547566.

It can be written as a sum of positive squares in 2 ways, for example, as 571305604 + 94439524 = 23902^2 + 9718^2 .

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, 12368 + ... + 38528.

Almost surely, 2^665745128 is an apocalyptic number.

It is an amenable number.

665745128 is a deficient number, since it is larger than the sum of its proper divisors (582967132).

665745128 is a wasteful number, since it uses less digits than its factorization.

665745128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29348 (or 29344 counting only the distinct ones).

The product of its digits is 403200, while the sum is 44.

The square root of 665745128 is about 25802.0372839045. The cubic root of 665745128 is about 873.1777600369.

The spelling of 665745128 in words is "six hundred sixty-five million, seven hundred forty-five thousand, one hundred twenty-eight".