209326945 has 24 divisors (see below), whose sum is σ = 263491704. Its totient is φ = 159584256.

The previous prime is 209326939. The next prime is 209326987. The reversal of 209326945 is 549623902.

It can be written as a sum of positive squares in 12 ways, for example, as 40742689 + 168584256 = 6383^2 + 12984^2 .

It is not a de Polignac number, because 209326945 - 2⁹ = 209326433 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 209326898 and 209326907.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 362497 + ... + 363073.

It is an arithmetic number, because the mean of its divisors is an integer number (10978821).

Almost surely, 2^209326945 is an apocalyptic number.

It is an amenable number.

209326945 is a deficient number, since it is larger than the sum of its proper divisors (54164759).

209326945 is an equidigital number, since it uses as much as digits as its factorization.

209326945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709 (or 672 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 40.

The square root of 209326945 is about 14468.1355053096. The cubic root of 209326945 is about 593.7565019417.

The spelling of 209326945 in words is "two hundred nine million, three hundred twenty-six thousand, nine hundred forty-five".