9781994 has 8 divisors (see below), whose sum is σ = 14710788. Its totient is φ = 4878400.

The previous prime is 9781991. The next prime is 9781997. The reversal of 9781994 is 4991879.

9781994 is nontrivially palindromic in base 3.

It is an interprime number because it is at equal distance from previous prime (9781991) and next prime (9781997).

It can be written as a sum of positive squares in 2 ways, for example, as 7924225 + 1857769 = 2815^2 + 1363^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9781991) 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, 5297 + ... + 6900.

Almost surely, 2^9781994 is an apocalyptic number.

9781994 is a deficient number, since it is larger than the sum of its proper divisors (4928794).

9781994 is a wasteful number, since it uses less digits than its factorization.

9781994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12600.

The product of its digits is 163296, while the sum is 47.

The square root of 9781994 is about 3127.6179434196. The cubic root of 9781994 is about 213.8663532137.

The spelling of 9781994 in words is "nine million, seven hundred eighty-one thousand, nine hundred ninety-four".