42443281 has 2 divisors, whose sum is σ = 42443282. Its totient is φ = 42443280.

The previous prime is 42443267. The next prime is 42443311. The reversal of 42443281 is 18234424.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30305025 + 12138256 = 5505^2 + 3484^2 .

It is a cyclic number.

It is not a de Polignac number, because 42443281 - 2⁵ = 42443249 is a prime.

It is a super-2 number, since 2×42443281² = 3602864204089922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (42443581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21221640 + 21221641.

It is an arithmetic number, because the mean of its divisors is an integer number (21221641).

Almost surely, 2^42443281 is an apocalyptic number.

It is an amenable number.

42443281 is a deficient number, since it is larger than the sum of its proper divisors (1).

42443281 is an equidigital number, since it uses as much as digits as its factorization.

42443281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6144, while the sum is 28.

The square root of 42443281 is about 6514.8508041244. The cubic root of 42443281 is about 348.8212892809.

It can be divided in two parts, 42443 and 281, that added together give a palindrome (42724).

The spelling of 42443281 in words is "forty-two million, four hundred forty-three thousand, two hundred eighty-one".