647869289 has 2 divisors, whose sum is σ = 647869290. Its totient is φ = 647869288.

The previous prime is 647869259. The next prime is 647869333. The reversal of 647869289 is 982968746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 615288025 + 32581264 = 24805^2 + 5708^2 .

It is a cyclic number.

It is not a de Polignac number, because 647869289 - 2¹² = 647865193 is a prime.

It is not a weakly prime, because it can be changed into another prime (647869259) 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, 323934644 + 323934645.

It is an arithmetic number, because the mean of its divisors is an integer number (323934645).

Almost surely, 2^647869289 is an apocalyptic number.

It is an amenable number.

647869289 is a deficient number, since it is larger than the sum of its proper divisors (1).

647869289 is an equidigital number, since it uses as much as digits as its factorization.

647869289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10450944, while the sum is 59.

The square root of 647869289 is about 25453.2765867187. The cubic root of 647869289 is about 865.2915537398.

The spelling of 647869289 in words is "six hundred forty-seven million, eight hundred sixty-nine thousand, two hundred eighty-nine".