666829 has 2 divisors, whose sum is σ = 666830. Its totient is φ = 666828.

The previous prime is 666823. The next prime is 666857. The reversal of 666829 is 928666.

666829 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., 562500 + 104329 = 750^2 + 323^2 .

It is a cyclic number.

It is not a de Polignac number, because 666829 - 2³ = 666821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333414 + 333415.

It is an arithmetic number, because the mean of its divisors is an integer number (333415).

2⁶⁶⁶⁸²⁹ is an apocalyptic number.

It is an amenable number.

666829 is a deficient number, since it is larger than the sum of its proper divisors (1).

666829 is an equidigital number, since it uses as much as digits as its factorization.

666829 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 37.

The square root of 666829 is about 816.5959833357. The cubic root of 666829 is about 87.3651364596.

The spelling of 666829 in words is "six hundred sixty-six thousand, eight hundred twenty-nine".