2139812639 has 4 divisors (see below), whose sum is σ = 2139938640. Its totient is φ = 2139686640.

The previous prime is 2139812581. The next prime is 2139812641. The reversal of 2139812639 is 9362189312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2139812639 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2139812639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2139812669) 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, 32654 + ... + 73115.

It is an arithmetic number, because the mean of its divisors is an integer number (534984660).

Almost surely, 2^2139812639 is an apocalyptic number.

2139812639 is a deficient number, since it is larger than the sum of its proper divisors (126001).

2139812639 is a wasteful number, since it uses less digits than its factorization.

2139812639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126000.

The product of its digits is 139968, while the sum is 44.

The square root of 2139812639 is about 46258.1088999540. The cubic root of 2139812639 is about 1288.6211332840.

The spelling of 2139812639 in words is "two billion, one hundred thirty-nine million, eight hundred twelve thousand, six hundred thirty-nine".