647663477 has 2 divisors, whose sum is σ = 647663478. Its totient is φ = 647663476.

The previous prime is 647663437. The next prime is 647663483. The reversal of 647663477 is 774366746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 625300036 + 22363441 = 25006^2 + 4729^2 .

It is a cyclic number.

It is not a de Polignac number, because 647663477 - 2¹⁰ = 647662453 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647663437) 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, 323831738 + 323831739.

It is an arithmetic number, because the mean of its divisors is an integer number (323831739).

Almost surely, 2^647663477 is an apocalyptic number.

It is an amenable number.

647663477 is a deficient number, since it is larger than the sum of its proper divisors (1).

647663477 is an equidigital number, since it uses as much as digits as its factorization.

647663477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3556224, while the sum is 50.

The square root of 647663477 is about 25449.2333283343. The cubic root of 647663477 is about 865.1999168157.

The spelling of 647663477 in words is "six hundred forty-seven million, six hundred sixty-three thousand, four hundred seventy-seven".