669278671 has 2 divisors, whose sum is σ = 669278672. Its totient is φ = 669278670.

The previous prime is 669278669. The next prime is 669278677. The reversal of 669278671 is 176872966.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669278671 - 2¹ = 669278669 is a prime.

Together with 669278669, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669278677) 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, 334639335 + 334639336.

It is an arithmetic number, because the mean of its divisors is an integer number (334639336).

Almost surely, 2^669278671 is an apocalyptic number.

669278671 is a deficient number, since it is larger than the sum of its proper divisors (1).

669278671 is an equidigital number, since it uses as much as digits as its factorization.

669278671 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1524096, while the sum is 52.

The square root of 669278671 is about 25870.4207735398. The cubic root of 669278671 is about 874.7198759356.

The spelling of 669278671 in words is "six hundred sixty-nine million, two hundred seventy-eight thousand, six hundred seventy-one".