648773809 has 4 divisors (see below), whose sum is σ = 663861616. Its totient is φ = 633686004.

The previous prime is 648773779. The next prime is 648773813. The reversal of 648773809 is 908377846.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 648773809 - 2²³ = 640385201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648770809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7543839 + ... + 7543924.

It is an arithmetic number, because the mean of its divisors is an integer number (165965404).

Almost surely, 2^648773809 is an apocalyptic number.

It is an amenable number.

648773809 is a deficient number, since it is larger than the sum of its proper divisors (15087807).

648773809 is a wasteful number, since it uses less digits than its factorization.

648773809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15087806.

The product of its (nonzero) digits is 2032128, while the sum is 52.

The square root of 648773809 is about 25471.0386321406. The cubic root of 648773809 is about 865.6940575419.

It can be divided in two parts, 64877 and 3809, that added together give a palindrome (68686).

The spelling of 648773809 in words is "six hundred forty-eight million, seven hundred seventy-three thousand, eight hundred nine".