42739 has 4 divisors (see below), whose sum is σ = 43360. Its totient is φ = 42120.

The previous prime is 42737. The next prime is 42743. The reversal of 42739 is 93724.

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

It is a cyclic number.

It is not a de Polignac number, because 42739 - 2¹ = 42737 is a prime.

It is a Duffinian number.

42739 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (42737) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192 + ... + 349.

It is an arithmetic number, because the mean of its divisors is an integer number (10840).

2⁴²⁷³⁹ is an apocalyptic number.

42739 is a deficient number, since it is larger than the sum of its proper divisors (621).

42739 is an equidigital number, since it uses as much as digits as its factorization.

42739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 620.

The product of its digits is 1512, while the sum is 25.

The square root of 42739 is about 206.7341287741. The cubic root of 42739 is about 34.9629539995.

It can be divided in two parts, 427 and 39, that multiplied together give a triangular number (16653 = T₁₈₂).

The spelling of 42739 in words is "forty-two thousand, seven hundred thirty-nine".