9986981 has 8 divisors (see below), whose sum is σ = 10257528. Its totient is φ = 9720000.

The previous prime is 9986941. The next prime is 9986987. The reversal of 9986981 is 1896899.

9986981 = T₂₀₈ + T₂₀₉ + ... + T₄₀₉.

It can be written as a sum of positive squares in 4 ways, for example, as 2512225 + 7474756 = 1585^2 + 2734^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 9986981 - 2⁶ = 9986917 is a prime.

It is a super-2 number, since 2×9986981² = 199479578988722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9986987) 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 7 ways as a sum of consecutive naturals, for example, 5351 + ... + 6971.

It is an arithmetic number, because the mean of its divisors is an integer number (1282191).

Almost surely, 2^9986981 is an apocalyptic number.

It is an amenable number.

9986981 is a deficient number, since it is larger than the sum of its proper divisors (270547).

9986981 is a wasteful number, since it uses less digits than its factorization.

9986981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783.

The product of its digits is 279936, while the sum is 50.

The square root of 9986981 is about 3160.2185051037. The cubic root of 9986981 is about 215.3499331159.

The spelling of 9986981 in words is "nine million, nine hundred eighty-six thousand, nine hundred eighty-one".