1689561 has 12 divisors (see below), whose sum is σ = 2454192. Its totient is φ = 1120056.

The previous prime is 1689553. The next prime is 1689601. The reversal of 1689561 is 1659861.

1689561 is a `hidden beast` number, since 16 + 89 + 561 = 666.

It is not a de Polignac number, because 1689561 - 2³ = 1689553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1689521) 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 in 11 ways as a sum of consecutive naturals, for example, 1630 + ... + 2456.

It is an arithmetic number, because the mean of its divisors is an integer number (204516).

2^1689561 is an apocalyptic number.

It is an amenable number.

1689561 is a deficient number, since it is larger than the sum of its proper divisors (764631).

1689561 is a wasteful number, since it uses less digits than its factorization.

1689561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060 (or 1057 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The square root of 1689561 is about 1299.8311428797. The cubic root of 1689561 is about 119.1035278243.

The spelling of 1689561 in words is "one million, six hundred eighty-nine thousand, five hundred sixty-one".