42172043 has 2 divisors, whose sum is σ = 42172044. Its totient is φ = 42172042.

The previous prime is 42172033. The next prime is 42172049. The reversal of 42172043 is 34027124.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42172043 is a prime.

It is not a weakly prime, because it can be changed into another prime (42172049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21086021 + 21086022.

It is an arithmetic number, because the mean of its divisors is an integer number (21086022).

Almost surely, 2^42172043 is an apocalyptic number.

42172043 is a deficient number, since it is larger than the sum of its proper divisors (1).

42172043 is an equidigital number, since it uses as much as digits as its factorization.

42172043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 42172043 is about 6494.0005389590. Note that the first 3 decimals coincide. The cubic root of 42172043 is about 348.0766417491.

Adding to 42172043 its reverse (34027124), we get a palindrome (76199167).

The spelling of 42172043 in words is "forty-two million, one hundred seventy-two thousand, forty-three".