667439648 has 18 divisors (see below), whose sum is σ = 1314309591. Its totient is φ = 333646752.

The previous prime is 667439609. The next prime is 667439659. The reversal of 667439648 is 846934766.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 333719824 + 333719824 = 18268^2 + 18268^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=18268.

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 667439648.

It is an unprimeable number.

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 2 ways as a sum of consecutive naturals, for example, 143861 + ... + 148427.

Almost surely, 2^667439648 is an apocalyptic number.

It is an amenable number.

667439648 is a deficient number, since it is larger than the sum of its proper divisors (646869943).

667439648 is an frugal number, since it uses more digits than its factorization.

667439648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9144 (or 4569 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 53.

The square root of 667439648 is about 25834.8533574317. The cubic root of 667439648 is about 873.9179650254.

The spelling of 667439648 in words is "six hundred sixty-seven million, four hundred thirty-nine thousand, six hundred forty-eight".