42117181 has 2 divisors, whose sum is σ = 42117182. Its totient is φ = 42117180.

The previous prime is 42117169. The next prime is 42117197. The reversal of 42117181 is 18171124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41809156 + 308025 = 6466^2 + 555^2 .

It is a cyclic number.

It is not a de Polignac number, because 42117181 - 2⁵ = 42117149 is a prime.

It is a super-2 number, since 2×42117181² = 3547713870773522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42117151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21058590 + 21058591.

It is an arithmetic number, because the mean of its divisors is an integer number (21058591).

Almost surely, 2^42117181 is an apocalyptic number.

It is an amenable number.

42117181 is a deficient number, since it is larger than the sum of its proper divisors (1).

42117181 is an equidigital number, since it uses as much as digits as its factorization.

42117181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 448, while the sum is 25.

The square root of 42117181 is about 6489.7751116660. The cubic root of 42117181 is about 347.9256375438.

The spelling of 42117181 in words is "forty-two million, one hundred seventeen thousand, one hundred eighty-one".