647336621 has 2 divisors, whose sum is σ = 647336622. Its totient is φ = 647336620.

The previous prime is 647336617. The next prime is 647336689. The reversal of 647336621 is 126633746.

647336621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 493328521 + 154008100 = 22211^2 + 12410^2 .

It is a cyclic number.

It is not a de Polignac number, because 647336621 - 2² = 647336617 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 (647336611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323668310 + 323668311.

It is an arithmetic number, because the mean of its divisors is an integer number (323668311).

Almost surely, 2^647336621 is an apocalyptic number.

It is an amenable number.

647336621 is a deficient number, since it is larger than the sum of its proper divisors (1).

647336621 is an equidigital number, since it uses as much as digits as its factorization.

647336621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 38.

The square root of 647336621 is about 25442.8107920489. The cubic root of 647336621 is about 865.0543456561.

The spelling of 647336621 in words is "six hundred forty-seven million, three hundred thirty-six thousand, six hundred twenty-one".