42231389 has 2 divisors, whose sum is σ = 42231390. Its totient is φ = 42231388.

The previous prime is 42231367. The next prime is 42231403. The reversal of 42231389 is 98313224.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41705764 + 525625 = 6458^2 + 725^2 .

It is a cyclic number.

It is not a de Polignac number, because 42231389 - 2¹² = 42227293 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42231359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21115694 + 21115695.

It is an arithmetic number, because the mean of its divisors is an integer number (21115695).

Almost surely, 2^42231389 is an apocalyptic number.

It is an amenable number.

42231389 is a deficient number, since it is larger than the sum of its proper divisors (1).

42231389 is an equidigital number, since it uses as much as digits as its factorization.

42231389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 32.

The square root of 42231389 is about 6498.5682269251. The cubic root of 42231389 is about 348.2398404999.

The spelling of 42231389 in words is "forty-two million, two hundred thirty-one thousand, three hundred eighty-nine".