65644672 has 16 divisors (see below), whose sum is σ = 130776750. Its totient is φ = 32822272.

The previous prime is 65644669. The next prime is 65644679. The reversal of 65644672 is 27644656.

It can be written as a sum of positive squares in only one way, i.e., 62346816 + 3297856 = 7896^2 + 1816^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is not an unprimeable number, because it can be changed into a prime (65644679) 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 as a sum of consecutive naturals, namely, 256297 + ... + 256552.

Almost surely, 2^65644672 is an apocalyptic number.

It is an amenable number.

65644672 is a deficient number, since it is larger than the sum of its proper divisors (65132078).

65644672 is an equidigital number, since it uses as much as digits as its factorization.

65644672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512863 (or 512851 counting only the distinct ones).

The product of its digits is 241920, while the sum is 40.

The square root of 65644672 is about 8102.1399642317. The cubic root of 65644672 is about 403.3974614394.

It can be divided in two parts, 6564 and 4672, that added together give a square (11236 = 106²).

The spelling of 65644672 in words is "sixty-five million, six hundred forty-four thousand, six hundred seventy-two".