865181121 has 32 divisors (see below), whose sum is σ = 1336876800. Its totient is φ = 487489536.

The previous prime is 865181089. The next prime is 865181147. The reversal of 865181121 is 121181568.

865181121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 865181121 - 2⁵ = 865181089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (865181021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 710305 + ... + 711521.

It is an arithmetic number, because the mean of its divisors is an integer number (41777400).

Almost surely, 2^865181121 is an apocalyptic number.

It is an amenable number.

865181121 is a deficient number, since it is larger than the sum of its proper divisors (471695679).

865181121 is a wasteful number, since it uses less digits than its factorization.

865181121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1673.

The product of its digits is 3840, while the sum is 33.

The square root of 865181121 is about 29413.9613279137. The cubic root of 865181121 is about 952.8744411363.

The spelling of 865181121 in words is "eight hundred sixty-five million, one hundred eighty-one thousand, one hundred twenty-one".