42172643 has 2 divisors, whose sum is σ = 42172644. Its totient is φ = 42172642.

The previous prime is 42172621. The next prime is 42172661. The reversal of 42172643 is 34627124.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42172643 - 2¹² = 42168547 is a prime.

It is not a weakly prime, because it can be changed into another prime (42172673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21086321 + 21086322.

It is an arithmetic number, because the mean of its divisors is an integer number (21086322).

Almost surely, 2^42172643 is an apocalyptic number.

42172643 is a deficient number, since it is larger than the sum of its proper divisors (1).

42172643 is an equidigital number, since it uses as much as digits as its factorization.

42172643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 29.

The square root of 42172643 is about 6494.0467352799. The cubic root of 42172643 is about 348.0782924872.

Adding to 42172643 its reverse (34627124), we get a palindrome (76799767).

The spelling of 42172643 in words is "forty-two million, one hundred seventy-two thousand, six hundred forty-three".