10865509 has 4 divisors (see below), whose sum is σ = 10874304. Its totient is φ = 10856716.

The previous prime is 10865471. The next prime is 10865557. The reversal of 10865509 is 90556801.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10865509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10865609) 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, 2167 + ... + 5140.

It is an arithmetic number, because the mean of its divisors is an integer number (2718576).

Almost surely, 2^10865509 is an apocalyptic number.

It is an amenable number.

10865509 is a deficient number, since it is larger than the sum of its proper divisors (8795).

10865509 is an equidigital number, since it uses as much as digits as its factorization.

10865509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8794.

The product of its (nonzero) digits is 10800, while the sum is 34.

The square root of 10865509 is about 3296.2871537534. The cubic root of 10865509 is about 221.4879101065.

The spelling of 10865509 in words is "ten million, eight hundred sixty-five thousand, five hundred nine".