989993 has 4 divisors (see below), whose sum is σ = 998868. Its totient is φ = 981120.

The previous prime is 989981. The next prime is 989999. The reversal of 989993 is 399989.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 43264 + 946729 = 208^2 + 973^2 .

It is a cyclic number.

It is not a de Polignac number, because 989993 - 2⁴ = 989977 is a prime.

It is a super-2 number, since 2×989993² = 1960172280098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (989999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4268 + ... + 4493.

It is an arithmetic number, because the mean of its divisors is an integer number (249717).

2⁹⁸⁹⁹⁹³ is an apocalyptic number.

It is an amenable number.

989993 is a deficient number, since it is larger than the sum of its proper divisors (8875).

989993 is a wasteful number, since it uses less digits than its factorization.

989993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8874.

The product of its digits is 157464, while the sum is 47.

The square root of 989993 is about 994.9839194680. The cubic root of 989993 is about 99.6653144387.

The spelling of 989993 in words is "nine hundred eighty-nine thousand, nine hundred ninety-three".