42946181 has 2 divisors, whose sum is σ = 42946182. Its totient is φ = 42946180.

The previous prime is 42946177. The next prime is 42946219. The reversal of 42946181 is 18164924.

It is a happy number.

42946181 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42902500 + 43681 = 6550^2 + 209^2 .

It is a cyclic number.

It is not a de Polignac number, because 42946181 - 2² = 42946177 is a prime.

It is a super-2 number, since 2×42946181² = 3688748924969522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42946171) 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, 21473090 + 21473091.

It is an arithmetic number, because the mean of its divisors is an integer number (21473091).

Almost surely, 2^42946181 is an apocalyptic number.

It is an amenable number.

42946181 is a deficient number, since it is larger than the sum of its proper divisors (1).

42946181 is an equidigital number, since it uses as much as digits as its factorization.

42946181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824, while the sum is 35.

The square root of 42946181 is about 6553.3335791794. Note that the first 3 decimals coincide. The cubic root of 42946181 is about 350.1935827069.

The spelling of 42946181 in words is "forty-two million, nine hundred forty-six thousand, one hundred eighty-one".