647622257 has 2 divisors, whose sum is σ = 647622258. Its totient is φ = 647622256.

The previous prime is 647622253. The next prime is 647622263. The reversal of 647622257 is 752226746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 484396081 + 163226176 = 22009^2 + 12776^2 .

It is a cyclic number.

It is not a de Polignac number, because 647622257 - 2² = 647622253 is a prime.

It is not a weakly prime, because it can be changed into another prime (647622251) 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, 323811128 + 323811129.

It is an arithmetic number, because the mean of its divisors is an integer number (323811129).

Almost surely, 2^647622257 is an apocalyptic number.

It is an amenable number.

647622257 is a deficient number, since it is larger than the sum of its proper divisors (1).

647622257 is an equidigital number, since it uses as much as digits as its factorization.

647622257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 282240, while the sum is 41.

The square root of 647622257 is about 25448.4234678693. The cubic root of 647622257 is about 865.1815614514.

The spelling of 647622257 in words is "six hundred forty-seven million, six hundred twenty-two thousand, two hundred fifty-seven".