125641209 has 4 divisors (see below), whose sum is σ = 167521616. Its totient is φ = 83760804.

The previous prime is 125641207. The next prime is 125641231. The reversal of 125641209 is 902146521.

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 not a de Polignac number, because 125641209 - 2¹ = 125641207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125641207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20940199 + ... + 20940204.

It is an arithmetic number, because the mean of its divisors is an integer number (41880404).

Almost surely, 2^125641209 is an apocalyptic number.

It is an amenable number.

125641209 is a deficient number, since it is larger than the sum of its proper divisors (41880407).

125641209 is an equidigital number, since it uses as much as digits as its factorization.

125641209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41880406.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 125641209 is about 11208.9789454705. The cubic root of 125641209 is about 500.8534876221.

The spelling of 125641209 in words is "one hundred twenty-five million, six hundred forty-one thousand, two hundred nine".