10505509 has 4 divisors (see below), whose sum is σ = 12006304. Its totient is φ = 9004716.

The previous prime is 10505491. The next prime is 10505527. The reversal of 10505509 is 90550501.

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: 90550501 = 353 ⋅256517.

It is an interprime number because it is at equal distance from previous prime (10505491) and next prime (10505527).

It is not a de Polignac number, because 10505509 - 2⁵ = 10505477 is a prime.

It is a super-2 number, since 2×10505509² = 220731438698162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10505909) 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, 750387 + ... + 750400.

It is an arithmetic number, because the mean of its divisors is an integer number (3001576).

Almost surely, 2^10505509 is an apocalyptic number.

It is an amenable number.

10505509 is a deficient number, since it is larger than the sum of its proper divisors (1500795).

10505509 is an equidigital number, since it uses as much as digits as its factorization.

10505509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1500794.

The product of its (nonzero) digits is 1125, while the sum is 25.

The square root of 10505509 is about 3241.2202948889. The cubic root of 10505509 is about 219.0142467605.

The spelling of 10505509 in words is "ten million, five hundred five thousand, five hundred nine".