981688 has 16 divisors (see below), whose sum is σ = 1851480. Its totient is φ = 487968.

The previous prime is 981683. The next prime is 981691. The reversal of 981688 is 886189.

It is a happy number.

It is a super-2 number, since 2×981688² = 1927422658688, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 981688.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981683) 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 3 ways as a sum of consecutive naturals, for example, 1995 + ... + 2437.

2⁹⁸¹⁶⁸⁸ is an apocalyptic number.

It is an amenable number.

981688 is a deficient number, since it is larger than the sum of its proper divisors (869792).

981688 is a wasteful number, since it uses less digits than its factorization.

981688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 726 (or 722 counting only the distinct ones).

The product of its digits is 27648, while the sum is 40.

The square root of 981688 is about 990.8016955981. The cubic root of 981688 is about 99.3858357447.

The spelling of 981688 in words is "nine hundred eighty-one thousand, six hundred eighty-eight".