665830889 has 4 divisors (see below), whose sum is σ = 700874640. Its totient is φ = 630787140.

The previous prime is 665830859. The next prime is 665830903. The reversal of 665830889 is 988038566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 665830889 - 2²⁴ = 649053673 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 665830889.

It is not an unprimeable number, because it can be changed into a prime (665830849) 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, 17521847 + ... + 17521884.

It is an arithmetic number, because the mean of its divisors is an integer number (175218660).

Almost surely, 2^665830889 is an apocalyptic number.

It is an amenable number.

665830889 is a deficient number, since it is larger than the sum of its proper divisors (35043751).

665830889 is a wasteful number, since it uses less digits than its factorization.

665830889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35043750.

The product of its (nonzero) digits is 2488320, while the sum is 53.

The square root of 665830889 is about 25803.6991340389. The cubic root of 665830889 is about 873.2152525544.

The spelling of 665830889 in words is "six hundred sixty-five million, eight hundred thirty thousand, eight hundred eighty-nine".