1689216449 has 2 divisors, whose sum is σ = 1689216450. Its totient is φ = 1689216448.

The previous prime is 1689216437. The next prime is 1689216497. The reversal of 1689216449 is 9446129861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 855855025 + 833361424 = 29255^2 + 28868^2 .

It is a cyclic number.

It is not a de Polignac number, because 1689216449 - 2¹² = 1689212353 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1689216397 and 1689216406.

It is not a weakly prime, because it can be changed into another prime (1689216499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844608224 + 844608225.

It is an arithmetic number, because the mean of its divisors is an integer number (844608225).

Almost surely, 2^1689216449 is an apocalyptic number.

It is an amenable number.

1689216449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1689216449 is an equidigital number, since it uses as much as digits as its factorization.

1689216449 is an evil number, because the sum of its binary digits is even.

The product of its digits is 746496, while the sum is 50.

The square root of 1689216449 is about 41100.0784549130. The cubic root of 1689216449 is about 1190.9543104070.

The spelling of 1689216449 in words is "one billion, six hundred eighty-nine million, two hundred sixteen thousand, four hundred forty-nine".