30181 has 2 divisors, whose sum is σ = 30182. Its totient is φ = 30180.

The previous prime is 30169. The next prime is 30187. The reversal of 30181 is 18103.

30181 is nontrivially palindromic in base 9.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25281 + 4900 = 159^2 + 70^2 .

It is a cyclic number.

It is not a de Polignac number, because 30181 - 2^{9} = 29669 is a prime.

It is a super-2 number, since 2×30181^{2} = 1821785522, which contains 22 as substring.

It is a Chen prime.

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

30181 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15090 + 15091.

It is an arithmetic number, because the mean of its divisors is an integer number (15091).

2^{30181} is an apocalyptic number.

It is an amenable number.

30181 is a deficient number, since it is larger than the sum of its proper divisors (1).

30181 is an equidigital number, since it uses as much as digits as its factorization.

30181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 30181 is about 173.7267970119. The cubic root of 30181 is about 31.1346897031.

Adding to 30181 its reverse (18103), we get a palindrome (48284).

The spelling of 30181 in words is "thirty thousand, one hundred eighty-one".

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