2109818 has 4 divisors (see below), whose sum is σ = 3164730. Its totient is φ = 1054908.

The previous prime is 2109799. The next prime is 2109841. The reversal of 2109818 is 8189012.

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

It can be written as a sum of positive squares in only one way, i.e., 1776889 + 332929 = 1333^2 + 577^2 .

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 527453 + ... + 527456.

2^2109818 is an apocalyptic number.

2109818 is a deficient number, since it is larger than the sum of its proper divisors (1054912).

2109818 is a wasteful number, since it uses less digits than its factorization.

2109818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1054911.

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 2109818 is about 1452.5212562989. The cubic root of 2109818 is about 128.2571733794.

The spelling of 2109818 in words is "two million, one hundred nine thousand, eight hundred eighteen".