181849221 has 12 divisors (see below), whose sum is σ = 278122572. Its totient is φ = 114101376.

The previous prime is 181849207. The next prime is 181849253. The reversal of 181849221 is 122948181.

It is a happy number.

181849221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 148498596 + 33350625 = 12186^2 + 5775^2 .

It is not a de Polignac number, because 181849221 - 2¹⁰ = 181848197 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181849271) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 594126 + ... + 594431.

It is an arithmetic number, because the mean of its divisors is an integer number (23176881).

Almost surely, 2^181849221 is an apocalyptic number.

It is an amenable number.

181849221 is a deficient number, since it is larger than the sum of its proper divisors (96273351).

181849221 is a wasteful number, since it uses less digits than its factorization.

181849221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1188580 (or 1188577 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 181849221 is about 13485.1481638134. The cubic root of 181849221 is about 566.5485708148.

The spelling of 181849221 in words is "one hundred eighty-one million, eight hundred forty-nine thousand, two hundred twenty-one".