2181687287839 has 2 divisors, whose sum is σ = 2181687287840. Its totient is φ = 2181687287838.

The previous prime is 2181687287789. The next prime is 2181687287893. The reversal of 2181687287839 is 9387827861812.

It is a happy number.

Together with next prime (2181687287893) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2181687287839 - 2⁹ = 2181687287327 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2181687287539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090843643919 + 1090843643920.

It is an arithmetic number, because the mean of its divisors is an integer number (1090843643920).

Almost surely, 2^{2181687287839} is an apocalyptic number.

2181687287839 is a deficient number, since it is larger than the sum of its proper divisors (1).

2181687287839 is an equidigital number, since it uses as much as digits as its factorization.

2181687287839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 130056192, while the sum is 70.

The spelling of 2181687287839 in words is "two trillion, one hundred eighty-one billion, six hundred eighty-seven million, two hundred eighty-seven thousand, eight hundred thirty-nine".