181531241 has 4 divisors (see below), whose sum is σ = 181830912. Its totient is φ = 181231572.

The previous prime is 181531193. The next prime is 181531243. The reversal of 181531241 is 142135181.

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 181531241 - 2¹⁸ = 181269097 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 181531241.

It is not an unprimeable number, because it can be changed into a prime (181531243) 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, 148925 + ... + 150138.

It is an arithmetic number, because the mean of its divisors is an integer number (45457728).

Almost surely, 2^181531241 is an apocalyptic number.

It is an amenable number.

181531241 is a deficient number, since it is larger than the sum of its proper divisors (299671).

181531241 is an equidigital number, since it uses as much as digits as its factorization.

181531241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 299670.

The product of its digits is 960, while the sum is 26.

The square root of 181531241 is about 13473.3529976766. The cubic root of 181531241 is about 566.2181574844.

The spelling of 181531241 in words is "one hundred eighty-one million, five hundred thirty-one thousand, two hundred forty-one".