42739661 has 4 divisors (see below), whose sum is σ = 42767772. Its totient is φ = 42711552.

The previous prime is 42739633. The next prime is 42739693. The reversal of 42739661 is 16693724.

42739661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33709636 + 9030025 = 5806^2 + 3005^2 .

It is a cyclic number.

It is not a de Polignac number, because 42739661 - 2¹⁰ = 42738637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42739601) 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 3 ways as a sum of consecutive naturals, for example, 11636 + ... + 14861.

It is an arithmetic number, because the mean of its divisors is an integer number (10691943).

Almost surely, 2^42739661 is an apocalyptic number.

It is an amenable number.

42739661 is a deficient number, since it is larger than the sum of its proper divisors (28111).

42739661 is a wasteful number, since it uses less digits than its factorization.

42739661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28110.

The product of its digits is 54432, while the sum is 38.

The square root of 42739661 is about 6537.5577244105. The cubic root of 42739661 is about 349.6313424389.

The spelling of 42739661 in words is "forty-two million, seven hundred thirty-nine thousand, six hundred sixty-one".