406666109 has 2 divisors, whose sum is σ = 406666110. Its totient is φ = 406666108.

The previous prime is 406666087. The next prime is 406666207. The reversal of 406666109 is 901666604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 387499225 + 19166884 = 19685^2 + 4378^2 .

It is a cyclic number.

It is not a de Polignac number, because 406666109 - 2¹² = 406662013 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (406663109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203333054 + 203333055.

It is an arithmetic number, because the mean of its divisors is an integer number (203333055).

Almost surely, 2^406666109 is an apocalyptic number.

It is an amenable number.

406666109 is a deficient number, since it is larger than the sum of its proper divisors (1).

406666109 is an equidigital number, since it uses as much as digits as its factorization.

406666109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 406666109 is about 20165.9641227490. The cubic root of 406666109 is about 740.8767967196.

The spelling of 406666109 in words is "four hundred six million, six hundred sixty-six thousand, one hundred nine".