2191839 has 16 divisors (see below), whose sum is σ = 3222912. Its totient is φ = 1316448.

The previous prime is 2191823. The next prime is 2191873. The reversal of 2191839 is 9381912.

It is not a de Polignac number, because 2191839 - 2⁴ = 2191823 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1024 + ... + 2330.

It is an arithmetic number, because the mean of its divisors is an integer number (201432).

2^2191839 is an apocalyptic number.

2191839 is a deficient number, since it is larger than the sum of its proper divisors (1031073).

2191839 is a wasteful number, since it uses less digits than its factorization.

2191839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1366.

The product of its digits is 3888, while the sum is 33.

The square root of 2191839 is about 1480.4860688301. The cubic root of 2191839 is about 129.8981253148.

The spelling of 2191839 in words is "two million, one hundred ninety-one thousand, eight hundred thirty-nine".