181169897 has 4 divisors (see below), whose sum is σ = 181526340. Its totient is φ = 180813456.

The previous prime is 181169869. The next prime is 181169899. The reversal of 181169897 is 798961181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 76230361 + 104939536 = 8731^2 + 10244^2 .

It is a cyclic number.

It is not a de Polignac number, because 181169897 - 2¹⁶ = 181104361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (181169899) 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, 177458 + ... + 178475.

It is an arithmetic number, because the mean of its divisors is an integer number (45381585).

Almost surely, 2^181169897 is an apocalyptic number.

It is an amenable number.

181169897 is a deficient number, since it is larger than the sum of its proper divisors (356443).

181169897 is an equidigital number, since it uses as much as digits as its factorization.

181169897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356442.

The product of its digits is 217728, while the sum is 50.

The square root of 181169897 is about 13459.9367383357. The cubic root of 181169897 is about 565.8422158794.

The spelling of 181169897 in words is "one hundred eighty-one million, one hundred sixty-nine thousand, eight hundred ninety-seven".