9129881 has 4 divisors (see below), whose sum is σ = 9137700. Its totient is φ = 9122064.

The previous prime is 9129877. The next prime is 9129893. The reversal of 9129881 is 1889219.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 225625 + 8904256 = 475^2 + 2984^2 .

It is a cyclic number.

It is not a de Polignac number, because 9129881 - 2² = 9129877 is a prime.

It is a super-2 number, since 2×9129881² = 166709454148322, 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 (9129811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1766 + ... + 4623.

It is an arithmetic number, because the mean of its divisors is an integer number (2284425).

Almost surely, 2^9129881 is an apocalyptic number.

It is an amenable number.

9129881 is a deficient number, since it is larger than the sum of its proper divisors (7819).

9129881 is a wasteful number, since it uses less digits than its factorization.

9129881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7818.

The product of its digits is 10368, while the sum is 38.

The square root of 9129881 is about 3021.5692942575. The cubic root of 9129881 is about 209.0042122729.

The spelling of 9129881 in words is "nine million, one hundred twenty-nine thousand, eight hundred eighty-one".