647929673 has 2 divisors, whose sum is σ = 647929674. Its totient is φ = 647929672.

The previous prime is 647929649. The next prime is 647929679. The reversal of 647929673 is 376929746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 644499769 + 3429904 = 25387^2 + 1852^2 .

It is a cyclic number.

It is not a de Polignac number, because 647929673 - 2¹⁰ = 647928649 is a prime.

It is a super-2 number, since 2×647929673² = 839625722307773858, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (647929679) 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, 323964836 + 323964837.

It is an arithmetic number, because the mean of its divisors is an integer number (323964837).

Almost surely, 2^647929673 is an apocalyptic number.

It is an amenable number.

647929673 is a deficient number, since it is larger than the sum of its proper divisors (1).

647929673 is an equidigital number, since it uses as much as digits as its factorization.

647929673 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3429216, while the sum is 53.

The square root of 647929673 is about 25454.4627324955. The cubic root of 647929673 is about 865.3184357786.

The spelling of 647929673 in words is "six hundred forty-seven million, nine hundred twenty-nine thousand, six hundred seventy-three".