2181239439 has 8 divisors (see below), whose sum is σ = 2935001520. Its totient is φ = 1440818496.

The previous prime is 2181239399. The next prime is 2181239443. The reversal of 2181239439 is 9349321812.

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

It is not a de Polignac number, because 2181239439 - 2¹⁹ = 2180715151 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2181239439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181239449) 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 7 ways as a sum of consecutive naturals, for example, 3334902 + ... + 3335555.

It is an arithmetic number, because the mean of its divisors is an integer number (366875190).

Almost surely, 2^2181239439 is an apocalyptic number.

2181239439 is a deficient number, since it is larger than the sum of its proper divisors (753762081).

2181239439 is a wasteful number, since it uses less digits than its factorization.

2181239439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6670569.

The product of its digits is 93312, while the sum is 42.

The square root of 2181239439 is about 46703.7411670628. The cubic root of 2181239439 is about 1296.8839449784.

The spelling of 2181239439 in words is "two billion, one hundred eighty-one million, two hundred thirty-nine thousand, four hundred thirty-nine".