42127021 has 2 divisors, whose sum is σ = 42127022. Its totient is φ = 42127020.

The previous prime is 42127013. The next prime is 42127031. The reversal of 42127021 is 12072124.

42127021 = 4589² + 4590².

It is a happy number.

42127021 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., 21068100 + 21058921 = 4590^2 + 4589^2 .

It is a cyclic number.

It is not a de Polignac number, because 42127021 - 2³ = 42127013 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42127021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42127031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21063510 + 21063511.

It is an arithmetic number, because the mean of its divisors is an integer number (21063511).

Almost surely, 2^42127021 is an apocalyptic number.

42127021 is the 4590-th centered square number.

It is an amenable number.

42127021 is a deficient number, since it is larger than the sum of its proper divisors (1).

42127021 is an equidigital number, since it uses as much as digits as its factorization.

42127021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 42127021 is about 6490.5331830290. The cubic root of 42127021 is about 347.9527311717.

Adding to 42127021 its reverse (12072124), we get a palindrome (54199145).

The spelling of 42127021 in words is "forty-two million, one hundred twenty-seven thousand, twenty-one".