667188377861 has 2 divisors, whose sum is σ = 667188377862. Its totient is φ = 667188377860.

The previous prime is 667188377833. The next prime is 667188377903. The reversal of 667188377861 is 168773881766.

667188377861 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., 487671772225 + 179516605636 = 698335^2 + 423694^2 .

It is a cyclic number.

It is not a de Polignac number, because 667188377861 - 2³⁰ = 666114636037 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 667188377791 and 667188377800.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667188376861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333594188930 + 333594188931.

It is an arithmetic number, because the mean of its divisors is an integer number (333594188931).

Almost surely, 2^667188377861 is an apocalyptic number.

It is an amenable number.

667188377861 is a deficient number, since it is larger than the sum of its proper divisors (1).

667188377861 is an equidigital number, since it uses as much as digits as its factorization.

667188377861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 113799168, while the sum is 68.

The spelling of 667188377861 in words is "six hundred sixty-seven billion, one hundred eighty-eight million, three hundred seventy-seven thousand, eight hundred sixty-one".