648381689609 has 4 divisors (see below), whose sum is σ = 648588381204. Its totient is φ = 648174998016.

The previous prime is 648381689597. The next prime is 648381689611. The reversal of 648381689609 is 906986183846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 906986183846 = 2 ⋅453493091923.

It can be written as a sum of positive squares in 2 ways, for example, as 360957035209 + 287424654400 = 600797^2 + 536120^2 .

It is a cyclic number.

It is not a de Polignac number, because 648381689609 - 2⁸ = 648381689353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648381689699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103341092 + ... + 103347365.

It is an arithmetic number, because the mean of its divisors is an integer number (162147095301).

Almost surely, 2^648381689609 is an apocalyptic number.

It is an amenable number.

648381689609 is a deficient number, since it is larger than the sum of its proper divisors (206691595).

648381689609 is a wasteful number, since it uses less digits than its factorization.

648381689609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206691594.

The product of its (nonzero) digits is 107495424, while the sum is 68.

The spelling of 648381689609 in words is "six hundred forty-eight billion, three hundred eighty-one million, six hundred eighty-nine thousand, six hundred nine".