684858901 has 2 divisors, whose sum is σ = 684858902. Its totient is φ = 684858900.

The previous prime is 684858899. The next prime is 684858907. The reversal of 684858901 is 109858486.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 567678276 + 117180625 = 23826^2 + 10825^2 .

It is a cyclic number.

It is not a de Polignac number, because 684858901 - 2¹ = 684858899 is a prime.

Together with 684858899, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (684858907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342429450 + 342429451.

It is an arithmetic number, because the mean of its divisors is an integer number (342429451).

Almost surely, 2^684858901 is an apocalyptic number.

It is an amenable number.

684858901 is a deficient number, since it is larger than the sum of its proper divisors (1).

684858901 is an equidigital number, since it uses as much as digits as its factorization.

684858901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 552960, while the sum is 49.

The square root of 684858901 is about 26169.8089599447. The cubic root of 684858901 is about 881.4554517475.

The spelling of 684858901 in words is "six hundred eighty-four million, eight hundred fifty-eight thousand, nine hundred one".