6918649 has 2 divisors, whose sum is σ = 6918650. Its totient is φ = 6918648.

The previous prime is 6918647. The next prime is 6918689. The reversal of 6918649 is 9468196.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4494400 + 2424249 = 2120^2 + 1557^2 .

It is a cyclic number.

It is not a de Polignac number, because 6918649 - 2¹ = 6918647 is a prime.

Together with 6918647, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6918647) 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, 3459324 + 3459325.

It is an arithmetic number, because the mean of its divisors is an integer number (3459325).

Almost surely, 2^6918649 is an apocalyptic number.

It is an amenable number.

6918649 is a deficient number, since it is larger than the sum of its proper divisors (1).

6918649 is an equidigital number, since it uses as much as digits as its factorization.

6918649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 6918649 is about 2630.3324884889. The cubic root of 6918649 is about 190.5491866937.

The spelling of 6918649 in words is "six million, nine hundred eighteen thousand, six hundred forty-nine".