648404689 has 2 divisors, whose sum is σ = 648404690. Its totient is φ = 648404688.

The previous prime is 648404663. The next prime is 648404741. The reversal of 648404689 is 986404846.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 551874064 + 96530625 = 23492^2 + 9825^2 .

It is a cyclic number.

It is not a de Polignac number, because 648404689 - 2¹¹ = 648402641 is a prime.

It is not a weakly prime, because it can be changed into another prime (648404609) 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 as a sum of consecutive naturals, namely, 324202344 + 324202345.

It is an arithmetic number, because the mean of its divisors is an integer number (324202345).

Almost surely, 2^648404689 is an apocalyptic number.

It is an amenable number.

648404689 is a deficient number, since it is larger than the sum of its proper divisors (1).

648404689 is an equidigital number, since it uses as much as digits as its factorization.

648404689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1327104, while the sum is 49.

The square root of 648404689 is about 25463.7917247216. The cubic root of 648404689 is about 865.5298474547.

The spelling of 648404689 in words is "six hundred forty-eight million, four hundred four thousand, six hundred eighty-nine".