209149 has 4 divisors (see below), whose sum is σ = 210400. Its totient is φ = 207900.

The previous prime is 209147. The next prime is 209159. The reversal of 209149 is 941902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 209149 - 2¹ = 209147 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209147) 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 3 ways as a sum of consecutive naturals, for example, 327 + ... + 724.

It is an arithmetic number, because the mean of its divisors is an integer number (52600).

2²⁰⁹¹⁴⁹ is an apocalyptic number.

It is an amenable number.

209149 is a deficient number, since it is larger than the sum of its proper divisors (1251).

209149 is a wasteful number, since it uses less digits than its factorization.

209149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1250.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 209149 is about 457.3281097855. The cubic root of 209149 is about 59.3588207071.

The spelling of 209149 in words is "two hundred nine thousand, one hundred forty-nine".