666658469 has 2 divisors, whose sum is σ = 666658470. Its totient is φ = 666658468.

The previous prime is 666658459. The next prime is 666658543. The reversal of 666658469 is 964856666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 626500900 + 40157569 = 25030^2 + 6337^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666658469 is a prime.

It is a super-2 number, since 2×666658469² = 888867028578847922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666658459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333329234 + 333329235.

It is an arithmetic number, because the mean of its divisors is an integer number (333329235).

Almost surely, 2^666658469 is an apocalyptic number.

It is an amenable number.

666658469 is a deficient number, since it is larger than the sum of its proper divisors (1).

666658469 is an equidigital number, since it uses as much as digits as its factorization.

666658469 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11197440, while the sum is 56.

The square root of 666658469 is about 25819.7302270957. The cubic root of 666658469 is about 873.5768840609.

The spelling of 666658469 in words is "six hundred sixty-six million, six hundred fifty-eight thousand, four hundred sixty-nine".