1689931 has 2 divisors, whose sum is σ = 1689932. Its totient is φ = 1689930.

The previous prime is 1689929. The next prime is 1689967. The reversal of 1689931 is 1399861.

It is a weak prime.

It is an emirp because it is prime and its reverse (1399861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1689931 - 2¹ = 1689929 is a prime.

It is a super-2 number, since 2×1689931² = 5711733569522, which contains 22 as substring.

Together with 1689929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1689911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844965 + 844966.

It is an arithmetic number, because the mean of its divisors is an integer number (844966).

2^1689931 is an apocalyptic number.

1689931 is a deficient number, since it is larger than the sum of its proper divisors (1).

1689931 is an equidigital number, since it uses as much as digits as its factorization.

1689931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 37.

The square root of 1689931 is about 1299.9734612676. The cubic root of 1689931 is about 119.1122214216.

The spelling of 1689931 in words is "one million, six hundred eighty-nine thousand, nine hundred thirty-one".