42705729 has 24 divisors (see below), whose sum is σ = 67976064. Its totient is φ = 25620000.

The previous prime is 42705721. The next prime is 42705739. The reversal of 42705729 is 92750724.

It is not a de Polignac number, because 42705729 - 2³ = 42705721 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42705693 and 42705702.

It is not an unprimeable number, because it can be changed into a prime (42705721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7864 + ... + 12134.

It is an arithmetic number, because the mean of its divisors is an integer number (2832336).

Almost surely, 2^42705729 is an apocalyptic number.

It is an amenable number.

42705729 is a deficient number, since it is larger than the sum of its proper divisors (25270335).

42705729 is a wasteful number, since it uses less digits than its factorization.

42705729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4389 (or 4386 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 42705729 is about 6534.9620503871. The cubic root of 42705729 is about 349.5387911533.

It can be divided in two parts, 42705 and 729, that added together give a palindrome (43434).

The spelling of 42705729 in words is "forty-two million, seven hundred five thousand, seven hundred twenty-nine".