1687728 has 40 divisors (see below), whose sum is σ = 4983808. Its totient is φ = 482112.

The previous prime is 1687669. The next prime is 1687729. The reversal of 1687728 is 8277861.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1687729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2176 + ... + 2847.

2^1687728 is an apocalyptic number.

It is an amenable number.

1687728 is an abundant number, since it is smaller than the sum of its proper divisors (3296080).

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

1687728 is a wasteful number, since it uses less digits than its factorization.

1687728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5041 (or 5035 counting only the distinct ones).

The product of its digits is 37632, while the sum is 39.

The square root of 1687728 is about 1299.1258599535. The cubic root of 1687728 is about 119.0604405441.

It can be divided in two parts, 1687 and 728, that added together give a triangular number (2415 = T₆₉).

The spelling of 1687728 in words is "one million, six hundred eighty-seven thousand, seven hundred twenty-eight".