667444109 has 2 divisors, whose sum is σ = 667444110. Its totient is φ = 667444108.

The previous prime is 667444097. The next prime is 667444177. The reversal of 667444109 is 901444766.

667444109 is digitally balanced in base 2, 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., 609349225 + 58094884 = 24685^2 + 7622^2 .

It is a cyclic number.

It is not a de Polignac number, because 667444109 - 2⁴ = 667444093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667444189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333722054 + 333722055.

It is an arithmetic number, because the mean of its divisors is an integer number (333722055).

Almost surely, 2^667444109 is an apocalyptic number.

It is an amenable number.

667444109 is a deficient number, since it is larger than the sum of its proper divisors (1).

667444109 is an equidigital number, since it uses as much as digits as its factorization.

667444109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 667444109 is about 25834.9396941429. The cubic root of 667444109 is about 873.9199120376.

The spelling of 667444109 in words is "six hundred sixty-seven million, four hundred forty-four thousand, one hundred nine".