181641497 has 4 divisors (see below), whose sum is σ = 181733136. Its totient is φ = 181549860.

The previous prime is 181641487. The next prime is 181641517. The reversal of 181641497 is 794146181.

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, and also an emirpimes, since its reverse is a distinct semiprime: 794146181 = 317 ⋅2505193.

It is a cyclic number.

It is not a de Polignac number, because 181641497 - 2⁸ = 181641241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (181641407) 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, 42779 + ... + 46832.

It is an arithmetic number, because the mean of its divisors is an integer number (45433284).

Almost surely, 2^181641497 is an apocalyptic number.

It is an amenable number.

181641497 is a deficient number, since it is larger than the sum of its proper divisors (91639).

181641497 is an equidigital number, since it uses as much as digits as its factorization.

181641497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91638.

The product of its digits is 48384, while the sum is 41.

The square root of 181641497 is about 13477.4440084164. Note that the first 3 decimals coincide. The cubic root of 181641497 is about 566.3327682699.

The spelling of 181641497 in words is "one hundred eighty-one million, six hundred forty-one thousand, four hundred ninety-seven".