84181 has 2 divisors, whose sum is σ = 84182. Its totient is φ = 84180.

The previous prime is 84179. The next prime is 84191. The reversal of 84181 is 18148.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84100 + 81 = 290^2 + 9^2 .

It is a cyclic number.

It is not a de Polignac number, because 84181 - 2¹ = 84179 is a prime.

It is a super-2 number, since 2×84181² = 14172881522, which contains 22 as substring.

Together with 84179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42090 + 42091.

It is an arithmetic number, because the mean of its divisors is an integer number (42091).

2⁸⁴¹⁸¹ is an apocalyptic number.

84181 is the 184-th centered pentagonal number.

It is an amenable number.

84181 is a deficient number, since it is larger than the sum of its proper divisors (1).

84181 is an equidigital number, since it uses as much as digits as its factorization.

84181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 256, while the sum is 22.

The square root of 84181 is about 290.1396215618. The cubic root of 84181 is about 43.8266249025.

It can be divided in two parts, 841 and 81, that multiplied together give a square (68121 = 261²).

The spelling of 84181 in words is "eighty-four thousand, one hundred eighty-one".