9981111 has 16 divisors (see below), whose sum is σ = 15257088. Its totient is φ = 5685600.

The previous prime is 9981079. The next prime is 9981121. The reversal of 9981111 is 1111899.

It is a happy number.

9981111 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9981111 - 2⁵ = 9981079 is a prime.

9981111 is a modest number, since divided by 1111 gives 998 as remainder.

9981111 is a lucky number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9981121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9166 + ... + 10196.

It is an arithmetic number, because the mean of its divisors is an integer number (953568).

Almost surely, 2^9981111 is an apocalyptic number.

9981111 is a deficient number, since it is larger than the sum of its proper divisors (5275977).

9981111 is a wasteful number, since it uses less digits than its factorization.

9981111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1502.

The product of its digits is 648, while the sum is 30.

The square root of 9981111 is about 3159.2896353453. The cubic root of 9981111 is about 215.3077331139.

The spelling of 9981111 in words is "nine million, nine hundred eighty-one thousand, one hundred eleven".