2191819 has 12 divisors (see below), whose sum is σ = 2614248. Its totient is φ = 1831200.

The previous prime is 2191811. The next prime is 2191823. The reversal of 2191819 is 9181912.

2191819 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2191819 - 2³ = 2191811 is a prime.

It is a super-2 number, since 2×2191819² = 9608141057522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191811) 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 11 ways as a sum of consecutive naturals, for example, 1464 + ... + 2554.

It is an arithmetic number, because the mean of its divisors is an integer number (217854).

2^2191819 is an apocalyptic number.

2191819 is a deficient number, since it is larger than the sum of its proper divisors (422429).

2191819 is a wasteful number, since it uses less digits than its factorization.

2191819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1146 (or 1139 counting only the distinct ones).

The product of its digits is 1296, while the sum is 31.

The square root of 2191819 is about 1480.4793142763. The cubic root of 2191819 is about 129.8977302173.

The spelling of 2191819 in words is "two million, one hundred ninety-one thousand, eight hundred nineteen".