42661243 has 2 divisors, whose sum is σ = 42661244. Its totient is φ = 42661242.

The previous prime is 42661207. The next prime is 42661247. The reversal of 42661243 is 34216624.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42661243 is a prime.

It is not a weakly prime, because it can be changed into another prime (42661247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21330621 + 21330622.

It is an arithmetic number, because the mean of its divisors is an integer number (21330622).

Almost surely, 2^42661243 is an apocalyptic number.

42661243 is a deficient number, since it is larger than the sum of its proper divisors (1).

42661243 is an equidigital number, since it uses as much as digits as its factorization.

42661243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6912, while the sum is 28.

The square root of 42661243 is about 6531.5574712315. The cubic root of 42661243 is about 349.4173789882.

Adding to 42661243 its reverse (34216624), we get a palindrome (76877867).

The spelling of 42661243 in words is "forty-two million, six hundred sixty-one thousand, two hundred forty-three".