647916673 has 2 divisors, whose sum is σ = 647916674. Its totient is φ = 647916672.

The previous prime is 647916671. The next prime is 647916713. The reversal of 647916673 is 376619746.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 582112129 + 65804544 = 24127^2 + 8112^2 .

It is a cyclic number.

It is not a de Polignac number, because 647916673 - 2¹ = 647916671 is a prime.

Together with 647916671, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (647916671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323958336 + 323958337.

It is an arithmetic number, because the mean of its divisors is an integer number (323958337).

Almost surely, 2^647916673 is an apocalyptic number.

It is an amenable number.

647916673 is a deficient number, since it is larger than the sum of its proper divisors (1).

647916673 is an equidigital number, since it uses as much as digits as its factorization.

647916673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1143072, while the sum is 49.

The square root of 647916673 is about 25454.2073732419. The cubic root of 647916673 is about 865.3126485173.

The spelling of 647916673 in words is "six hundred forty-seven million, nine hundred sixteen thousand, six hundred seventy-three".