665982469 has 4 divisors (see below), whose sum is σ = 670452300. Its totient is φ = 661512640.

The previous prime is 665982467. The next prime is 665982481. The reversal of 665982469 is 964289566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 964289566 = 2 ⋅482144783.

It can be written as a sum of positive squares in 2 ways, for example, as 359557444 + 306425025 = 18962^2 + 17505^2 .

It is a cyclic number.

It is not a de Polignac number, because 665982469 - 2¹ = 665982467 is a prime.

It is a super-2 number, since 2×665982469² = 887065298030671922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665982467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2234692 + ... + 2234989.

It is an arithmetic number, because the mean of its divisors is an integer number (167613075).

Almost surely, 2^665982469 is an apocalyptic number.

It is an amenable number.

665982469 is a deficient number, since it is larger than the sum of its proper divisors (4469831).

665982469 is a wasteful number, since it uses less digits than its factorization.

665982469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4469830.

The product of its digits is 5598720, while the sum is 55.

The square root of 665982469 is about 25806.6361426669. The cubic root of 665982469 is about 873.2815115836.

The spelling of 665982469 in words is "six hundred sixty-five million, nine hundred eighty-two thousand, four hundred sixty-nine".