42517021 has 2 divisors, whose sum is σ = 42517022. Its totient is φ = 42517020.

The previous prime is 42516989. The next prime is 42517039. The reversal of 42517021 is 12071524.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41100921 + 1416100 = 6411^2 + 1190^2 .

It is a cyclic number.

It is not a de Polignac number, because 42517021 - 2⁵ = 42516989 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 42516983 and 42517001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42517091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21258510 + 21258511.

It is an arithmetic number, because the mean of its divisors is an integer number (21258511).

Almost surely, 2^42517021 is an apocalyptic number.

It is an amenable number.

42517021 is a deficient number, since it is larger than the sum of its proper divisors (1).

42517021 is an equidigital number, since it uses as much as digits as its factorization.

42517021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 42517021 is about 6520.5077256300. The cubic root of 42517021 is about 349.0231838196.

Adding to 42517021 its reverse (12071524), we get a palindrome (54588545).

The spelling of 42517021 in words is "forty-two million, five hundred seventeen thousand, twenty-one".