1689987065 has 12 divisors (see below), whose sum is σ = 2184411684. Its totient is φ = 1247745696.

The previous prime is 1689987049. The next prime is 1689987071. The reversal of 1689987065 is 5607899861.

It can be written as a sum of positive squares in 2 ways, for example, as 415996816 + 1273990249 = 20396^2 + 35693^2 .

It is not a de Polignac number, because 1689987065 - 2⁴ = 1689987049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1689986995 and 1689987013.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 328886 + ... + 333984.

It is an arithmetic number, because the mean of its divisors is an integer number (182034307).

Almost surely, 2^1689987065 is an apocalyptic number.

It is an amenable number.

1689987065 is a deficient number, since it is larger than the sum of its proper divisors (494424619).

1689987065 is an frugal number, since it uses more digits than its factorization.

1689987065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10216 (or 5117 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 59.

The square root of 1689987065 is about 41109.4522585743. The cubic root of 1689987065 is about 1191.1353862586.

The spelling of 1689987065 in words is "one billion, six hundred eighty-nine million, nine hundred eighty-seven thousand, sixty-five".