209426 has 12 divisors (see below), whose sum is σ = 365598. Its totient is φ = 89712.

The previous prime is 209401. The next prime is 209431. The reversal of 209426 is 624902.

It can be written as a sum of positive squares in only one way, i.e., 207025 + 2401 = 455^2 + 49^2 .

It is an Ulam number.

It is a plaindrome in base 11.

It is an unprimeable number.

209426 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 971 + ... + 1166.

2²⁰⁹⁴²⁶ is an apocalyptic number.

209426 is a deficient number, since it is larger than the sum of its proper divisors (156172).

209426 is a wasteful number, since it uses less digits than its factorization.

209426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2153 (or 2146 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 209426 is about 457.6308556031. The cubic root of 209426 is about 59.3850143773.

The spelling of 209426 in words is "two hundred nine thousand, four hundred twenty-six".