42000521 has 2 divisors, whose sum is σ = 42000522. Its totient is φ = 42000520.

The previous prime is 42000503. The next prime is 42000529. The reversal of 42000521 is 12500024.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29855296 + 12145225 = 5464^2 + 3485^2 .

It is a cyclic number.

It is not a de Polignac number, because 42000521 - 2⁶ = 42000457 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42000496 and 42000505.

It is not a weakly prime, because it can be changed into another prime (42000529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21000260 + 21000261.

It is an arithmetic number, because the mean of its divisors is an integer number (21000261).

Almost surely, 2^42000521 is an apocalyptic number.

It is an amenable number.

42000521 is a deficient number, since it is larger than the sum of its proper divisors (1).

42000521 is an equidigital number, since it uses as much as digits as its factorization.

42000521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 42000521 is about 6480.7808943059. The cubic root of 42000521 is about 347.6041017921.

Adding to 42000521 its reverse (12500024), we get a palindrome (54500545).

The spelling of 42000521 in words is "forty-two million, five hundred twenty-one", and thus it is an aban number.