647341729 has 2 divisors, whose sum is σ = 647341730. Its totient is φ = 647341728.

The previous prime is 647341727. The next prime is 647341753. The reversal of 647341729 is 927143746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 433597329 + 213744400 = 20823^2 + 14620^2 .

It is a cyclic number.

It is not a de Polignac number, because 647341729 - 2¹ = 647341727 is a prime.

Together with 647341727, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (647341727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323670864 + 323670865.

It is an arithmetic number, because the mean of its divisors is an integer number (323670865).

Almost surely, 2^647341729 is an apocalyptic number.

It is an amenable number.

647341729 is a deficient number, since it is larger than the sum of its proper divisors (1).

647341729 is an equidigital number, since it uses as much as digits as its factorization.

647341729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 43.

The square root of 647341729 is about 25442.9111738417. The cubic root of 647341729 is about 865.0566209720.

The spelling of 647341729 in words is "six hundred forty-seven million, three hundred forty-one thousand, seven hundred twenty-nine".