42020254021 has 2 divisors, whose sum is σ = 42020254022. Its totient is φ = 42020254020.

The previous prime is 42020254007. The next prime is 42020254063. The reversal of 42020254021 is 12045202024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22639716225 + 19380537796 = 150465^2 + 139214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42020254021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42020253983 and 42020254001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42020254721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21010127010 + 21010127011.

It is an arithmetic number, because the mean of its divisors is an integer number (21010127011).

Almost surely, 2^42020254021 is an apocalyptic number.

It is an amenable number.

42020254021 is a deficient number, since it is larger than the sum of its proper divisors (1).

42020254021 is an equidigital number, since it uses as much as digits as its factorization.

42020254021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1280, while the sum is 22.

Adding to 42020254021 its reverse (12045202024), we get a palindrome (54065456045).

The spelling of 42020254021 in words is "forty-two billion, twenty million, two hundred fifty-four thousand, twenty-one".