981993 has 4 divisors (see below), whose sum is σ = 1309328. Its totient is φ = 654660.

The previous prime is 981983. The next prime is 982021. The reversal of 981993 is 399189.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 981993 - 2⁵ = 981961 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981913) 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, 163663 + ... + 163668.

It is an arithmetic number, because the mean of its divisors is an integer number (327332).

2⁹⁸¹⁹⁹³ is an apocalyptic number.

It is an amenable number.

981993 is a deficient number, since it is larger than the sum of its proper divisors (327335).

981993 is a wasteful number, since it uses less digits than its factorization.

981993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327334.

The product of its digits is 17496, while the sum is 39.

The square root of 981993 is about 990.9555994090. The cubic root of 981993 is about 99.3961273856.

The spelling of 981993 in words is "nine hundred eighty-one thousand, nine hundred ninety-three".