648818665 has 16 divisors (see below), whose sum is σ = 850927680. Its totient is φ = 470998720.

The previous prime is 648818663. The next prime is 648818683. The reversal of 648818665 is 566818846.

It is not a de Polignac number, because 648818665 - 2¹ = 648818663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (648818663) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 20046 + ... + 41224.

It is an arithmetic number, because the mean of its divisors is an integer number (53182980).

Almost surely, 2^648818665 is an apocalyptic number.

It is an amenable number.

648818665 is a deficient number, since it is larger than the sum of its proper divisors (202109015).

648818665 is a wasteful number, since it uses less digits than its factorization.

648818665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21752.

The product of its digits is 2211840, while the sum is 52.

The square root of 648818665 is about 25471.9191463855. The cubic root of 648818665 is about 865.7140083462.

The spelling of 648818665 in words is "six hundred forty-eight million, eight hundred eighteen thousand, six hundred sixty-five".