2091899 has 4 divisors (see below), whose sum is σ = 2094960. Its totient is φ = 2088840.

The previous prime is 2091889. The next prime is 2091913. The reversal of 2091899 is 9981902.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2091899 - 2²⁰ = 1043323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2091809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17 + ... + 2045.

It is an arithmetic number, because the mean of its divisors is an integer number (523740).

2^2091899 is an apocalyptic number.

2091899 is a deficient number, since it is larger than the sum of its proper divisors (3061).

2091899 is a wasteful number, since it uses less digits than its factorization.

2091899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3060.

The product of its (nonzero) digits is 11664, while the sum is 38.

The square root of 2091899 is about 1446.3398632410. The cubic root of 2091899 is about 127.8930380847.

It can be divided in two parts, 20 and 91899, that added together give a palindrome (91919).

The spelling of 2091899 in words is "two million, ninety-one thousand, eight hundred ninety-nine".