6687357409 has 2 divisors, whose sum is σ = 6687357410. Its totient is φ = 6687357408.

The previous prime is 6687357403. The next prime is 6687357421. The reversal of 6687357409 is 9047537866.

It is a happy number.

6687357409 is digitally balanced in base 3, 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., 4952218384 + 1735139025 = 70372^2 + 41655^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6687357409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6687357409.

It is not a weakly prime, because it can be changed into another prime (6687357403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3343678704 + 3343678705.

It is an arithmetic number, because the mean of its divisors is an integer number (3343678705).

Almost surely, 2^6687357409 is an apocalyptic number.

It is an amenable number.

6687357409 is a deficient number, since it is larger than the sum of its proper divisors (1).

6687357409 is an equidigital number, since it uses as much as digits as its factorization.

6687357409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7620480, while the sum is 55.

The square root of 6687357409 is about 81776.2643375203. The cubic root of 6687357409 is about 1884.0171203083.

The spelling of 6687357409 in words is "six billion, six hundred eighty-seven million, three hundred fifty-seven thousand, four hundred nine".