665606513 has 8 divisors (see below), whose sum is σ = 781971456. Its totient is φ = 558550800.

The previous prime is 665606507. The next prime is 665606519. The reversal of 665606513 is 315606566.

It is an interprime number because it is at equal distance from previous prime (665606507) and next prime (665606519).

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

It is a cyclic number.

It is not a de Polignac number, because 665606513 - 2⁸ = 665606257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665606519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2327153 + ... + 2327438.

It is an arithmetic number, because the mean of its divisors is an integer number (97746432).

Almost surely, 2^665606513 is an apocalyptic number.

It is an amenable number.

665606513 is a deficient number, since it is larger than the sum of its proper divisors (116364943).

665606513 is a wasteful number, since it uses less digits than its factorization.

665606513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4654615.

The product of its (nonzero) digits is 97200, while the sum is 38.

The square root of 665606513 is about 25799.3510189695. The cubic root of 665606513 is about 873.1171542929.

The spelling of 665606513 in words is "six hundred sixty-five million, six hundred six thousand, five hundred thirteen".