667178542991 has 2 divisors, whose sum is σ = 667178542992. Its totient is φ = 667178542990.

The previous prime is 667178542903. The next prime is 667178543039. The reversal of 667178542991 is 199245871766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 667178542991 - 2³⁸ = 392300636047 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667178542691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333589271495 + 333589271496.

It is an arithmetic number, because the mean of its divisors is an integer number (333589271496).

Almost surely, 2^667178542991 is an apocalyptic number.

667178542991 is a deficient number, since it is larger than the sum of its proper divisors (1).

667178542991 is an equidigital number, since it uses as much as digits as its factorization.

667178542991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45722880, while the sum is 65.

The spelling of 667178542991 in words is "six hundred sixty-seven billion, one hundred seventy-eight million, five hundred forty-two thousand, nine hundred ninety-one".