118242181 has 2 divisors, whose sum is σ = 118242182. Its totient is φ = 118242180.

The previous prime is 118242167. The next prime is 118242197. The reversal of 118242181 is 181242811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 118069956 + 172225 = 10866^2 + 415^2 .

It is an emirp because it is prime and its reverse (181242811) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 118242181 - 2¹⁷ = 118111109 is a prime.

It is a super-2 number, since 2×118242181² = 27962426735273522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (118242101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 59121090 + 59121091.

It is an arithmetic number, because the mean of its divisors is an integer number (59121091).

Almost surely, 2^118242181 is an apocalyptic number.

It is an amenable number.

118242181 is a deficient number, since it is larger than the sum of its proper divisors (1).

118242181 is an equidigital number, since it uses as much as digits as its factorization.

118242181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1024, while the sum is 28.

The square root of 118242181 is about 10873.9220615195. The cubic root of 118242181 is about 490.8221391815.

Adding to 118242181 its reverse (181242811), we get a palindrome (299484992).

The spelling of 118242181 in words is "one hundred eighteen million, two hundred forty-two thousand, one hundred eighty-one".