42581173 has 2 divisors, whose sum is σ = 42581174. Its totient is φ = 42581172.

The previous prime is 42581171. The next prime is 42581179. The reversal of 42581173 is 37118524.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35307364 + 7273809 = 5942^2 + 2697^2 .

It is a cyclic number.

It is not a de Polignac number, because 42581173 - 2¹ = 42581171 is a prime.

Together with 42581171, 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 (42581171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21290586 + 21290587.

It is an arithmetic number, because the mean of its divisors is an integer number (21290587).

Almost surely, 2^42581173 is an apocalyptic number.

It is an amenable number.

42581173 is a deficient number, since it is larger than the sum of its proper divisors (1).

42581173 is an equidigital number, since it uses as much as digits as its factorization.

42581173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6720, while the sum is 31.

The square root of 42581173 is about 6525.4251202508. The cubic root of 42581173 is about 349.1986373426.

Adding to 42581173 its reverse (37118524), we get a palindrome (79699697).

The spelling of 42581173 in words is "forty-two million, five hundred eighty-one thousand, one hundred seventy-three".