10505209 has 12 divisors (see below), whose sum is σ = 12411792. Its totient is φ = 8814000.

The previous prime is 10505207. The next prime is 10505263. The reversal of 10505209 is 90250501.

10505209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 10505209 - 2¹ = 10505207 is a prime.

It is a super-2 number, since 2×10505209² = 220718832267362, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 10505209.

It is not an unprimeable number, because it can be changed into a prime (10505207) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 967 + ... + 4684.

It is an arithmetic number, because the mean of its divisors is an integer number (1034316).

Almost surely, 2^10505209 is an apocalyptic number.

It is an amenable number.

10505209 is a deficient number, since it is larger than the sum of its proper divisors (1906583).

10505209 is a wasteful number, since it uses less digits than its factorization.

10505209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5688 (or 5675 counting only the distinct ones).

The product of its (nonzero) digits is 450, while the sum is 22.

The square root of 10505209 is about 3241.1740156925. The cubic root of 10505209 is about 219.0121619845.

The spelling of 10505209 in words is "ten million, five hundred five thousand, two hundred nine".