42809281 has 12 divisors (see below), whose sum is σ = 45799488. Its totient is φ = 40004672.

The previous prime is 42809269. The next prime is 42809293. The reversal of 42809281 is 18290824.

42809281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (42809269) and next prime (42809293).

It is not a de Polignac number, because 42809281 - 2²¹ = 40712129 is a prime.

It is a super-2 number, since 2×42809281² = 3665269079473922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42809201) 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 in 11 ways as a sum of consecutive naturals, for example, 47820 + ... + 48706.

It is an arithmetic number, because the mean of its divisors is an integer number (3816624).

Almost surely, 2^42809281 is an apocalyptic number.

It is an amenable number.

42809281 is a deficient number, since it is larger than the sum of its proper divisors (2990207).

42809281 is a wasteful number, since it uses less digits than its factorization.

42809281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1088 (or 1071 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 42809281 is about 6542.8801761915. The cubic root of 42809281 is about 349.8210813422.

The spelling of 42809281 in words is "forty-two million, eight hundred nine thousand, two hundred eighty-one".