648664915 has 4 divisors (see below), whose sum is σ = 778397904. Its totient is φ = 518931928.

The previous prime is 648664909. The next prime is 648664927. The reversal of 648664915 is 519466846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 519466846 = 2 ⋅259733423.

It is a cyclic number.

It is not a de Polignac number, because 648664915 - 2¹¹ = 648662867 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64866487 + ... + 64866496.

It is an arithmetic number, because the mean of its divisors is an integer number (194599476).

Almost surely, 2^648664915 is an apocalyptic number.

648664915 is a deficient number, since it is larger than the sum of its proper divisors (129732989).

648664915 is a wasteful number, since it uses less digits than its factorization.

648664915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129732988.

The product of its digits is 1244160, while the sum is 49.

The square root of 648664915 is about 25468.9009382030. The cubic root of 648664915 is about 865.6456204431.

The spelling of 648664915 in words is "six hundred forty-eight million, six hundred sixty-four thousand, nine hundred fifteen".