6721002016209 has 24 divisors (see below), whose sum is σ = 11069885677032. Its totient is φ = 3892707048960.

The previous prime is 6721002016187. The next prime is 6721002016219. The reversal of 6721002016209 is 9026102001276.

6721002016209 is a `hidden beast` number, since 6 + 7 + 2 + 1 + 0 + 0 + 20 + 1 + 620 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2729285723025 + 3991716293184 = 1652055^2 + 1997928^2 .

It is not a de Polignac number, because 6721002016209 - 2¹⁵ = 6721001983441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6721002016219) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1689541002 + ... + 1689544979.

It is an arithmetic number, because the mean of its divisors is an integer number (461245236543).

Almost surely, 2^{6721002016209} is an apocalyptic number.

It is an amenable number.

6721002016209 is a deficient number, since it is larger than the sum of its proper divisors (4348883660823).

6721002016209 is a wasteful number, since it uses less digits than its factorization.

6721002016209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3379086017 (or 3379086014 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The spelling of 6721002016209 in words is "six trillion, seven hundred twenty-one billion, two million, sixteen thousand, two hundred nine".