666877117 has 2 divisors, whose sum is σ = 666877118. Its totient is φ = 666877116.

The previous prime is 666877033. The next prime is 666877171. The reversal of 666877117 is 711778666.

Together with next prime (666877171) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 659154276 + 7722841 = 25674^2 + 2779^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666877117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666877187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333438558 + 333438559.

It is an arithmetic number, because the mean of its divisors is an integer number (333438559).

Almost surely, 2^666877117 is an apocalyptic number.

It is an amenable number.

666877117 is a deficient number, since it is larger than the sum of its proper divisors (1).

666877117 is an equidigital number, since it uses as much as digits as its factorization.

666877117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 592704, while the sum is 49.

The square root of 666877117 is about 25823.9640063256. The cubic root of 666877117 is about 873.6723777154.

The spelling of 666877117 in words is "six hundred sixty-six million, eight hundred seventy-seven thousand, one hundred seventeen".