11809897 has 4 divisors (see below), whose sum is σ = 12883536. Its totient is φ = 10736260.

The previous prime is 11809871. The next prime is 11809913. The reversal of 11809897 is 79890811.

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 a cyclic number.

It is not a de Polignac number, because 11809897 - 2⁷ = 11809769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11809807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 536803 + ... + 536824.

It is an arithmetic number, because the mean of its divisors is an integer number (3220884).

Almost surely, 2^11809897 is an apocalyptic number.

It is an amenable number.

11809897 is a deficient number, since it is larger than the sum of its proper divisors (1073639).

11809897 is a wasteful number, since it uses less digits than its factorization.

11809897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1073638.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 11809897 is about 3436.5530695742. The cubic root of 11809897 is about 227.7274431092.

It can be divided in two parts, 11 and 809897, that added together give a palindrome (809908).

The spelling of 11809897 in words is "eleven million, eight hundred nine thousand, eight hundred ninety-seven".