126209289 has 4 divisors (see below), whose sum is σ = 168279056. Its totient is φ = 84139524.

The previous prime is 126209287. The next prime is 126209323. The reversal of 126209289 is 982902621.

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, and also an emirpimes, since its reverse is a distinct semiprime: 982902621 = 3 ⋅327634207.

It is not a de Polignac number, because 126209289 - 2¹ = 126209287 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126209287) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 21034879 + ... + 21034884.

It is an arithmetic number, because the mean of its divisors is an integer number (42069764).

Almost surely, 2^126209289 is an apocalyptic number.

It is an amenable number.

126209289 is a deficient number, since it is larger than the sum of its proper divisors (42069767).

126209289 is an equidigital number, since it uses as much as digits as its factorization.

126209289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42069766.

The product of its (nonzero) digits is 31104, while the sum is 39.

The square root of 126209289 is about 11234.2907653309. The cubic root of 126209289 is about 501.6072135272.

The spelling of 126209289 in words is "one hundred twenty-six million, two hundred nine thousand, two hundred eighty-nine".