1669689443 has 2 divisors, whose sum is σ = 1669689444. Its totient is φ = 1669689442.

The previous prime is 1669689409. The next prime is 1669689473. The reversal of 1669689443 is 3449869661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1669689443 - 2²⁰ = 1668640867 is a prime.

It is not a weakly prime, because it can be changed into another prime (1669689473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834844721 + 834844722.

It is an arithmetic number, because the mean of its divisors is an integer number (834844722).

Almost surely, 2^1669689443 is an apocalyptic number.

1669689443 is a deficient number, since it is larger than the sum of its proper divisors (1).

1669689443 is an equidigital number, since it uses as much as digits as its factorization.

1669689443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6718464, while the sum is 56.

The square root of 1669689443 is about 40861.8335736418. The cubic root of 1669689443 is about 1186.3474481267.

The spelling of 1669689443 in words is "one billion, six hundred sixty-nine million, six hundred eighty-nine thousand, four hundred forty-three".