42639 has 8 divisors (see below), whose sum is σ = 58032. Its totient is φ = 27840.

The previous prime is 42611. The next prime is 42641. The reversal of 42639 is 93624.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42639 - 2¹¹ = 40591 is a prime.

It is a plaindrome in base 14.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 42639.

It is not an unprimeable number, because it can be changed into a prime (42649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67 + ... + 299.

It is an arithmetic number, because the mean of its divisors is an integer number (7254).

2⁴²⁶³⁹ is an apocalyptic number.

42639 is a deficient number, since it is larger than the sum of its proper divisors (15393).

42639 is a wasteful number, since it uses less digits than its factorization.

42639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297.

The product of its digits is 1296, while the sum is 24.

The square root of 42639 is about 206.4921306007. The cubic root of 42639 is about 34.9356641252.

It can be divided in two parts, 426 and 39, that added together give a triangular number (465 = T₃₀).

The spelling of 42639 in words is "forty-two thousand, six hundred thirty-nine".