42021349 has 2 divisors, whose sum is σ = 42021350. Its totient is φ = 42021348.

The previous prime is 42021347. The next prime is 42021359. The reversal of 42021349 is 94312024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37736449 + 4284900 = 6143^2 + 2070^2 .

It is a cyclic number.

It is not a de Polignac number, because 42021349 - 2¹ = 42021347 is a prime.

Together with 42021347, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42021341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21010674 + 21010675.

It is an arithmetic number, because the mean of its divisors is an integer number (21010675).

Almost surely, 2^42021349 is an apocalyptic number.

It is an amenable number.

42021349 is a deficient number, since it is larger than the sum of its proper divisors (1).

42021349 is an equidigital number, since it uses as much as digits as its factorization.

42021349 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 42021349 is about 6482.3876002596. The cubic root of 42021349 is about 347.6615510939.

The spelling of 42021349 in words is "forty-two million, twenty-one thousand, three hundred forty-nine".