42506210521 has 2 divisors, whose sum is σ = 42506210522. Its totient is φ = 42506210520.

The previous prime is 42506210501. The next prime is 42506210557. The reversal of 42506210521 is 12501260524.

42506210521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29673852121 + 12832358400 = 172261^2 + 113280^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42506210521 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42506210521.

It is not a weakly prime, because it can be changed into another prime (42506210501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21253105260 + 21253105261.

It is an arithmetic number, because the mean of its divisors is an integer number (21253105261).

Almost surely, 2^42506210521 is an apocalyptic number.

It is an amenable number.

42506210521 is a deficient number, since it is larger than the sum of its proper divisors (1).

42506210521 is an equidigital number, since it uses as much as digits as its factorization.

42506210521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4800, while the sum is 28.

The spelling of 42506210521 in words is "forty-two billion, five hundred six million, two hundred ten thousand, five hundred twenty-one".