181651121 has 4 divisors (see below), whose sum is σ = 181945200. Its totient is φ = 181357044.

The previous prime is 181651097. The next prime is 181651163. The reversal of 181651121 is 121156181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 181651121 - 2¹⁰ = 181650097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (181651321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 146111 + ... + 147348.

It is an arithmetic number, because the mean of its divisors is an integer number (45486300).

Almost surely, 2^181651121 is an apocalyptic number.

It is an amenable number.

181651121 is a deficient number, since it is larger than the sum of its proper divisors (294079).

181651121 is an equidigital number, since it uses as much as digits as its factorization.

181651121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294078.

The product of its digits is 480, while the sum is 26.

The square root of 181651121 is about 13477.8010446808. The cubic root of 181651121 is about 566.3427701883.

The spelling of 181651121 in words is "one hundred eighty-one million, six hundred fifty-one thousand, one hundred twenty-one".