667578971 has 2 divisors, whose sum is σ = 667578972. Its totient is φ = 667578970.

The previous prime is 667578953. The next prime is 667578973. The reversal of 667578971 is 179875766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 667578971 - 2⁶ = 667578907 is a prime.

Together with 667578973, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (667578973) 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, 333789485 + 333789486.

It is an arithmetic number, because the mean of its divisors is an integer number (333789486).

Almost surely, 2^667578971 is an apocalyptic number.

667578971 is a deficient number, since it is larger than the sum of its proper divisors (1).

667578971 is an equidigital number, since it uses as much as digits as its factorization.

667578971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4445280, while the sum is 56.

The square root of 667578971 is about 25837.5496322697. The cubic root of 667578971 is about 873.9787687260.

The spelling of 667578971 in words is "six hundred sixty-seven million, five hundred seventy-eight thousand, nine hundred seventy-one".