209440249 has 4 divisors (see below), whose sum is σ = 220463440. Its totient is φ = 198417060.

The previous prime is 209440237. The next prime is 209440261. The reversal of 209440249 is 942044902.

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 an interprime number because it is at equal distance from previous prime (209440237) and next prime (209440261).

It is a cyclic number.

It is not a de Polignac number, because 209440249 - 2¹³ = 209432057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209440279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5511567 + ... + 5511604.

It is an arithmetic number, because the mean of its divisors is an integer number (55115860).

Almost surely, 2^209440249 is an apocalyptic number.

It is an amenable number.

209440249 is a deficient number, since it is larger than the sum of its proper divisors (11023191).

209440249 is a wasteful number, since it uses less digits than its factorization.

209440249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11023190.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 209440249 is about 14472.0506148921. The cubic root of 209440249 is about 593.8636116630.

The spelling of 209440249 in words is "two hundred nine million, four hundred forty thousand, two hundred forty-nine".