10121209 has 4 divisors (see below), whose sum is σ = 11567104. Its totient is φ = 8675316.

The previous prime is 10121183. The next prime is 10121233. The reversal of 10121209 is 90212101.

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: 90212101 = 7 ⋅12887443.

It is a cyclic number.

It is not a de Polignac number, because 10121209 - 2⁹ = 10120697 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10121192 and 10121201.

It is not an unprimeable number, because it can be changed into a prime (10121299) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 722937 + ... + 722950.

It is an arithmetic number, because the mean of its divisors is an integer number (2891776).

Almost surely, 2^10121209 is an apocalyptic number.

It is an amenable number.

10121209 is a deficient number, since it is larger than the sum of its proper divisors (1445895).

10121209 is an equidigital number, since it uses as much as digits as its factorization.

10121209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1445894.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 10121209 is about 3181.3847613893. The cubic root of 10121209 is about 216.3104318392.

The spelling of 10121209 in words is "ten million, one hundred twenty-one thousand, two hundred nine".