665498107 has 4 divisors (see below), whose sum is σ = 665562600. Its totient is φ = 665433616.

The previous prime is 665498081. The next prime is 665498131. The reversal of 665498107 is 701894566.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a 4-Lehmer number, since φ(665498107) divides (665498107-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 665498107 - 2²³ = 657109499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665496107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12898 + ... + 38695.

It is an arithmetic number, because the mean of its divisors is an integer number (166390650).

It is a Poulet number, since it divides 2^665498106-1.

Almost surely, 2^665498107 is an apocalyptic number.

665498107 is the 12899-th decagonal number.

665498107 is a deficient number, since it is larger than the sum of its proper divisors (64493).

665498107 is a wasteful number, since it uses less digits than its factorization.

665498107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64492.

The product of its (nonzero) digits is 362880, while the sum is 46.

The square root of 665498107 is about 25797.2499890977. The cubic root of 665498107 is about 873.0697507718.

The spelling of 665498107 in words is "six hundred sixty-five million, four hundred ninety-eight thousand, one hundred seven".