684208913 has 2 divisors, whose sum is σ = 684208914. Its totient is φ = 684208912.

The previous prime is 684208907. The next prime is 684208937. The reversal of 684208913 is 319802486.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 389983504 + 294225409 = 19748^2 + 17153^2 .

It is a cyclic number.

It is not a de Polignac number, because 684208913 - 2⁴ = 684208897 is a prime.

It is not a weakly prime, because it can be changed into another prime (684208013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342104456 + 342104457.

It is an arithmetic number, because the mean of its divisors is an integer number (342104457).

Almost surely, 2^684208913 is an apocalyptic number.

It is an amenable number.

684208913 is a deficient number, since it is larger than the sum of its proper divisors (1).

684208913 is an equidigital number, since it uses as much as digits as its factorization.

684208913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 684208913 is about 26157.3873504217. The cubic root of 684208913 is about 881.1765053273.

The spelling of 684208913 in words is "six hundred eighty-four million, two hundred eight thousand, nine hundred thirteen".