665960506 has 8 divisors (see below), whose sum is σ = 999207540. Its totient is φ = 332891328.

The previous prime is 665960497. The next prime is 665960509. The reversal of 665960506 is 605069566.

It can be written as a sum of positive squares in 2 ways, for example, as 641862225 + 24098281 = 25335^2 + 4909^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (665960509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34671 + ... + 50338.

Almost surely, 2^665960506 is an apocalyptic number.

665960506 is a deficient number, since it is larger than the sum of its proper divisors (333247034).

665960506 is a wasteful number, since it uses less digits than its factorization.

665960506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88928.

The product of its (nonzero) digits is 291600, while the sum is 43.

The square root of 665960506 is about 25806.2106090763. The cubic root of 665960506 is about 873.2719116849.

The spelling of 665960506 in words is "six hundred sixty-five million, nine hundred sixty thousand, five hundred six".