1687968 has 36 divisors (see below), whose sum is σ = 4800978. Its totient is φ = 562560.

The previous prime is 1687963. The next prime is 1687969. The reversal of 1687968 is 8697861.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1468944 + 219024 = 1212^2 + 468^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (1687963) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2643 + ... + 3218.

2^1687968 is an apocalyptic number.

1687968 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1687968 is an abundant number, since it is smaller than the sum of its proper divisors (3113010).

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

1687968 is a wasteful number, since it uses less digits than its factorization.

1687968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5877 (or 5866 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 1687968 is about 1299.2182264731. The cubic root of 1687968 is about 119.0660838610.

The spelling of 1687968 in words is "one million, six hundred eighty-seven thousand, nine hundred sixty-eight".