1671689 has 2 divisors, whose sum is σ = 1671690. Its totient is φ = 1671688.

The previous prime is 1671679. The next prime is 1671707. The reversal of 1671689 is 9861761.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1646089 + 25600 = 1283^2 + 160^2 .

It is a cyclic number.

It is not a de Polignac number, because 1671689 - 2¹⁶ = 1606153 is a prime.

It is a super-2 number, since 2×1671689² = 5589088225442, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1671619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 835844 + 835845.

It is an arithmetic number, because the mean of its divisors is an integer number (835845).

2^1671689 is an apocalyptic number.

It is an amenable number.

1671689 is a deficient number, since it is larger than the sum of its proper divisors (1).

1671689 is an equidigital number, since it uses as much as digits as its factorization.

1671689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 38.

The square root of 1671689 is about 1292.9381269032. The cubic root of 1671689 is about 118.6820834169.

The spelling of 1671689 in words is "one million, six hundred seventy-one thousand, six hundred eighty-nine".