181630109 has 2 divisors, whose sum is σ = 181630110. Its totient is φ = 181630108.

The previous prime is 181630093. The next prime is 181630117. The reversal of 181630109 is 901036181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180902500 + 727609 = 13450^2 + 853^2 .

It is an emirp because it is prime and its reverse (901036181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181630109 - 2⁴ = 181630093 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181630129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90815054 + 90815055.

It is an arithmetic number, because the mean of its divisors is an integer number (90815055).

Almost surely, 2^181630109 is an apocalyptic number.

It is an amenable number.

181630109 is a deficient number, since it is larger than the sum of its proper divisors (1).

181630109 is an equidigital number, since it uses as much as digits as its factorization.

181630109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 181630109 is about 13477.0215181248. The cubic root of 181630109 is about 566.3209326258.

The spelling of 181630109 in words is "one hundred eighty-one million, six hundred thirty thousand, one hundred nine".