993681 has 32 divisors (see below), whose sum is σ = 1680000. Its totient is φ = 575424.

The previous prime is 993679. The next prime is 993683. The reversal of 993681 is 186399.

993681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (993679) and next prime (993683).

It is not a de Polignac number, because 993681 - 2¹ = 993679 is a prime.

It is a super-2 number, since 2×993681² = 1974803859522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (993683) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6595 + ... + 6743.

It is an arithmetic number, because the mean of its divisors is an integer number (52500).

2⁹⁹³⁶⁸¹ is an apocalyptic number.

It is an amenable number.

993681 is a deficient number, since it is larger than the sum of its proper divisors (686319).

993681 is a wasteful number, since it uses less digits than its factorization.

993681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190 (or 184 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 993681 is about 996.8354929476. The cubic root of 993681 is about 99.7889214386.

The spelling of 993681 in words is "nine hundred ninety-three thousand, six hundred eighty-one".