665657725 has 12 divisors (see below), whose sum is σ = 827446420. Its totient is φ = 531216000.

The previous prime is 665657719. The next prime is 665657749. The reversal of 665657725 is 527756566.

It can be written as a sum of positive squares in 6 ways, for example, as 55666521 + 609991204 = 7461^2 + 24698^2 .

It is not a de Polignac number, because 665657725 - 2³ = 665657717 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22326 + ... + 42775.

Almost surely, 2^665657725 is an apocalyptic number.

It is an amenable number.

665657725 is a deficient number, since it is larger than the sum of its proper divisors (161788695).

665657725 is a wasteful number, since it uses less digits than its factorization.

665657725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65520 (or 65515 counting only the distinct ones).

The product of its digits is 2646000, while the sum is 49.

The square root of 665657725 is about 25800.3435054652. The cubic root of 665657725 is about 873.1395463659.

The spelling of 665657725 in words is "six hundred sixty-five million, six hundred fifty-seven thousand, seven hundred twenty-five".