665488623 has 16 divisors (see below), whose sum is σ = 959265920. Its totient is φ = 408947616.

The previous prime is 665488619. The next prime is 665488631. The reversal of 665488623 is 326884566.

It is not a de Polignac number, because 665488623 - 2² = 665488619 is a prime.

It is a super-2 number, since 2×665488623² = 885750214684872258, which contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665488423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 155665 + ... + 159882.

It is an arithmetic number, because the mean of its divisors is an integer number (59954120).

Almost surely, 2^665488623 is an apocalyptic number.

665488623 is a deficient number, since it is larger than the sum of its proper divisors (293777297).

665488623 is a wasteful number, since it uses less digits than its factorization.

665488623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315606.

The product of its digits is 1658880, while the sum is 48.

The square root of 665488623 is about 25797.0661704001. The cubic root of 665488623 is about 873.0656033856.

The spelling of 665488623 in words is "six hundred sixty-five million, four hundred eighty-eight thousand, six hundred twenty-three".