647771243257 has 2 divisors, whose sum is σ = 647771243258. Its totient is φ = 647771243256.

The previous prime is 647771243239. The next prime is 647771243269. The reversal of 647771243257 is 752342177746.

647771243257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 635621913081 + 12149330176 = 797259^2 + 110224^2 .

It is a cyclic number.

It is not a de Polignac number, because 647771243257 - 2³⁵ = 613411504889 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 647771243198 and 647771243207.

It is not a weakly prime, because it can be changed into another prime (647771243857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323885621628 + 323885621629.

It is an arithmetic number, because the mean of its divisors is an integer number (323885621629).

Almost surely, 2^647771243257 is an apocalyptic number.

It is an amenable number.

647771243257 is a deficient number, since it is larger than the sum of its proper divisors (1).

647771243257 is an equidigital number, since it uses as much as digits as its factorization.

647771243257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13829760, while the sum is 55.

The spelling of 647771243257 in words is "six hundred forty-seven billion, seven hundred seventy-one million, two hundred forty-three thousand, two hundred fifty-seven".