993691 has 4 divisors (see below), whose sum is σ = 996592. Its totient is φ = 990792.

The previous prime is 993689. The next prime is 993703. The reversal of 993691 is 196399.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 196399 = 7 ⋅28057.

It is a cyclic number.

It is not a de Polignac number, because 993691 - 2¹ = 993689 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 993691.

It is not an unprimeable number, because it can be changed into a prime (993611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 855 + ... + 1648.

It is an arithmetic number, because the mean of its divisors is an integer number (249148).

2⁹⁹³⁶⁹¹ is an apocalyptic number.

993691 is a deficient number, since it is larger than the sum of its proper divisors (2901).

993691 is a wasteful number, since it uses less digits than its factorization.

993691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2900.

The product of its digits is 13122, while the sum is 37.

The square root of 993691 is about 996.8405088077. The cubic root of 993691 is about 99.7892561824.

The spelling of 993691 in words is "nine hundred ninety-three thousand, six hundred ninety-one".