647647706477 has 2 divisors, whose sum is σ = 647647706478. Its totient is φ = 647647706476.

The previous prime is 647647706471. The next prime is 647647706507. The reversal of 647647706477 is 774607746746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 461413167076 + 186234539401 = 679274^2 + 431549^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647647706477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647647706471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323823853238 + 323823853239.

It is an arithmetic number, because the mean of its divisors is an integer number (323823853239).

Almost surely, 2^647647706477 is an apocalyptic number.

It is an amenable number.

647647706477 is a deficient number, since it is larger than the sum of its proper divisors (1).

647647706477 is an equidigital number, since it uses as much as digits as its factorization.

647647706477 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 232339968, while the sum is 65.

The spelling of 647647706477 in words is "six hundred forty-seven billion, six hundred forty-seven million, seven hundred six thousand, four hundred seventy-seven".