42821993 has 2 divisors, whose sum is σ = 42821994. Its totient is φ = 42821992.

The previous prime is 42821983. The next prime is 42822001. The reversal of 42821993 is 39912824.

42821993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41113744 + 1708249 = 6412^2 + 1307^2 .

It is a cyclic number.

It is not a de Polignac number, because 42821993 - 2¹⁰ = 42820969 is a prime.

It is not a weakly prime, because it can be changed into another prime (42821903) 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, 21410996 + 21410997.

It is an arithmetic number, because the mean of its divisors is an integer number (21410997).

Almost surely, 2^42821993 is an apocalyptic number.

It is an amenable number.

42821993 is a deficient number, since it is larger than the sum of its proper divisors (1).

42821993 is an equidigital number, since it uses as much as digits as its factorization.

42821993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 38.

The square root of 42821993 is about 6543.8515417146. The cubic root of 42821993 is about 349.8557037838.

The spelling of 42821993 in words is "forty-two million, eight hundred twenty-one thousand, nine hundred ninety-three".