649209859 has 2 divisors, whose sum is σ = 649209860. Its totient is φ = 649209858.

The previous prime is 649209851. The next prime is 649209959. The reversal of 649209859 is 958902946.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 649209859 - 2³ = 649209851 is a prime.

It is not a weakly prime, because it can be changed into another prime (649209851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324604929 + 324604930.

It is an arithmetic number, because the mean of its divisors is an integer number (324604930).

Almost surely, 2^649209859 is an apocalyptic number.

649209859 is a deficient number, since it is larger than the sum of its proper divisors (1).

649209859 is an equidigital number, since it uses as much as digits as its factorization.

649209859 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1399680, while the sum is 52.

The square root of 649209859 is about 25479.5969159640. The cubic root of 649209859 is about 865.8879624895.

The spelling of 649209859 in words is "six hundred forty-nine million, two hundred nine thousand, eight hundred fifty-nine".