1669669081 has 2 divisors, whose sum is σ = 1669669082. Its totient is φ = 1669669080.

The previous prime is 1669669073. The next prime is 1669669087. The reversal of 1669669081 is 1809669661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1291755481 + 377913600 = 35941^2 + 19440^2 .

It is an emirp because it is prime and its reverse (1809669661) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1806996991 and 1996996081.

It is a cyclic number.

It is not a de Polignac number, because 1669669081 - 2³ = 1669669073 is a prime.

It is a super-2 number, since 2×1669669081² = 5575589680094769122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1669669087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834834540 + 834834541.

It is an arithmetic number, because the mean of its divisors is an integer number (834834541).

Almost surely, 2^1669669081 is an apocalyptic number.

It is an amenable number.

1669669081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1669669081 is an equidigital number, since it uses as much as digits as its factorization.

1669669081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 839808, while the sum is 52.

The square root of 1669669081 is about 40861.5844161726. The cubic root of 1669669081 is about 1186.3426255722.

The spelling of 1669669081 in words is "one billion, six hundred sixty-nine million, six hundred sixty-nine thousand, eighty-one".