65603665 has 16 divisors (see below), whose sum is σ = 80586576. Its totient is φ = 51251200.

The previous prime is 65603651. The next prime is 65603669. The reversal of 65603665 is 56630656.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 123201 + 65480464 = 351^2 + 8092^2 .

It is not a de Polignac number, because 65603665 - 2⁷ = 65603537 is a prime.

It is a super-3 number, since 3×65603665³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65603669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74025 + ... + 74905.

It is an arithmetic number, because the mean of its divisors is an integer number (5036661).

Almost surely, 2^65603665 is an apocalyptic number.

It is an amenable number.

65603665 is a deficient number, since it is larger than the sum of its proper divisors (14982911).

65603665 is a wasteful number, since it uses less digits than its factorization.

65603665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1220.

The product of its (nonzero) digits is 97200, while the sum is 37.

The square root of 65603665 is about 8099.6089411773. The cubic root of 65603665 is about 403.3134456571.

The spelling of 65603665 in words is "sixty-five million, six hundred three thousand, six hundred sixty-five".