1691369 has 2 divisors, whose sum is σ = 1691370. Its totient is φ = 1691368.

The previous prime is 1691359. The next prime is 1691387. The reversal of 1691369 is 9631961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1690000 + 1369 = 1300^2 + 37^2 .

It is a cyclic number.

It is not a de Polignac number, because 1691369 - 2⁸ = 1691113 is a prime.

It is a super-2 number, since 2×1691369² = 5721458188322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1691359) 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, 845684 + 845685.

It is an arithmetic number, because the mean of its divisors is an integer number (845685).

2^1691369 is an apocalyptic number.

It is an amenable number.

1691369 is a deficient number, since it is larger than the sum of its proper divisors (1).

1691369 is an equidigital number, since it uses as much as digits as its factorization.

1691369 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8748, while the sum is 35.

The square root of 1691369 is about 1300.5264318729. The cubic root of 1691369 is about 119.1459969257.

It can be divided in two parts, 169 and 1369, that multiplied together give a square (231361 = 481²).

The spelling of 1691369 in words is "one million, six hundred ninety-one thousand, three hundred sixty-nine".