1689456 has 40 divisors (see below), whose sum is σ = 4443664. Its totient is φ = 552960.

The previous prime is 1689451. The next prime is 1689497. The reversal of 1689456 is 6549861.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1689451) 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 in 7 ways as a sum of consecutive naturals, for example, 2640 + ... + 3216.

2^1689456 is an apocalyptic number.

1689456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1689456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2221832).

1689456 is an abundant number, since it is smaller than the sum of its proper divisors (2754208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1689456 is a wasteful number, since it uses less digits than its factorization.

1689456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649 (or 643 counting only the distinct ones).

The product of its digits is 51840, while the sum is 39.

The square root of 1689456 is about 1299.7907523906. The cubic root of 1689456 is about 119.1010604912.

It can be divided in two parts, 1689 and 456, that added together give a triangular number (2145 = T₆₅).

The spelling of 1689456 in words is "one million, six hundred eighty-nine thousand, four hundred fifty-six".