647966617 has 2 divisors, whose sum is σ = 647966618. Its totient is φ = 647966616.

The previous prime is 647966587. The next prime is 647966629. The reversal of 647966617 is 716669746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 501580816 + 146385801 = 22396^2 + 12099^2 .

It is a cyclic number.

It is not a de Polignac number, because 647966617 - 2¹⁵ = 647933849 is a prime.

It is not a weakly prime, because it can be changed into another prime (647966117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323983308 + 323983309.

It is an arithmetic number, because the mean of its divisors is an integer number (323983309).

Almost surely, 2^647966617 is an apocalyptic number.

It is an amenable number.

647966617 is a deficient number, since it is larger than the sum of its proper divisors (1).

647966617 is an equidigital number, since it uses as much as digits as its factorization.

647966617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 52.

The square root of 647966617 is about 25455.1884102240. The cubic root of 647966617 is about 865.3348818622.

The spelling of 647966617 in words is "six hundred forty-seven million, nine hundred sixty-six thousand, six hundred seventeen".