9981389181 has 8 divisors (see below), whose sum is σ = 13346653600. Its totient is φ = 6635192112.

The previous prime is 9981389167. The next prime is 9981389213. The reversal of 9981389181 is 1819831899.

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

It is not a de Polignac number, because 9981389181 - 2¹⁷ = 9981258109 is a prime.

It is a super-2 number, since 2×9981389181² (a number of 21 digits) 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 (9981389581) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4765615 + ... + 4767708.

It is an arithmetic number, because the mean of its divisors is an integer number (1668331700).

Almost surely, 2^9981389181 is an apocalyptic number.

It is an amenable number.

9981389181 is a deficient number, since it is larger than the sum of its proper divisors (3365264419).

9981389181 is a wasteful number, since it uses less digits than its factorization.

9981389181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9533675.

The product of its digits is 1119744, while the sum is 57.

The square root of 9981389181 is about 99906.9025693420. The cubic root of 9981389181 is about 2153.0973335764.

The spelling of 9981389181 in words is "nine billion, nine hundred eighty-one million, three hundred eighty-nine thousand, one hundred eighty-one".