2113209 has 20 divisors (see below), whose sum is σ = 3608704. Its totient is φ = 1207224.

The previous prime is 2113207. The next prime is 2113211. The reversal of 2113209 is 9023112.

It is a happy number.

2113209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (2113207) and next prime (2113211).

It is not a de Polignac number, because 2113209 - 2¹ = 2113207 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2113191 and 2113200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2113207) 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 19 ways as a sum of consecutive naturals, for example, 1297 + ... + 2430.

2^2113209 is an apocalyptic number.

It is an amenable number.

2113209 is a deficient number, since it is larger than the sum of its proper divisors (1495495).

2113209 is an equidigital number, since it uses as much as digits as its factorization.

2113209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3746 (or 3737 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 2113209 is about 1453.6880683283. The cubic root of 2113209 is about 128.3258502786.

Subtracting 2113209 from its reverse (9023112), we obtain a triangular number (6909903 = T₃₇₁₇).

The spelling of 2113209 in words is "two million, one hundred thirteen thousand, two hundred nine".