42923021 has 2 divisors, whose sum is σ = 42923022. Its totient is φ = 42923020.

The previous prime is 42923017. The next prime is 42923029. The reversal of 42923021 is 12032924.

42923021 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., 33988900 + 8934121 = 5830^2 + 2989^2 .

It is a cyclic number.

It is not a de Polignac number, because 42923021 - 2² = 42923017 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a plaindrome in base 11.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42923029) 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, 21461510 + 21461511.

It is an arithmetic number, because the mean of its divisors is an integer number (21461511).

Almost surely, 2^42923021 is an apocalyptic number.

It is an amenable number.

42923021 is a deficient number, since it is larger than the sum of its proper divisors (1).

42923021 is an equidigital number, since it uses as much as digits as its factorization.

42923021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 42923021 is about 6551.5663012748. The cubic root of 42923021 is about 350.1306206338.

Adding to 42923021 its reverse (12032924), we get a palindrome (54955945).

The spelling of 42923021 in words is "forty-two million, nine hundred twenty-three thousand, twenty-one".