669631843 has 2 divisors, whose sum is σ = 669631844. Its totient is φ = 669631842.

The previous prime is 669631841. The next prime is 669631861. The reversal of 669631843 is 348136966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669631843 - 2¹ = 669631841 is a prime.

Together with 669631841, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 669631793 and 669631802.

It is not a weakly prime, because it can be changed into another prime (669631841) 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, 334815921 + 334815922.

It is an arithmetic number, because the mean of its divisors is an integer number (334815922).

Almost surely, 2^669631843 is an apocalyptic number.

669631843 is a deficient number, since it is larger than the sum of its proper divisors (1).

669631843 is an equidigital number, since it uses as much as digits as its factorization.

669631843 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 559872, while the sum is 46.

The square root of 669631843 is about 25877.2456610050. The cubic root of 669631843 is about 874.8737093377.

The spelling of 669631843 in words is "six hundred sixty-nine million, six hundred thirty-one thousand, eight hundred forty-three".