11815897 has 4 divisors (see below), whose sum is σ = 11823076. Its totient is φ = 11808720.

The previous prime is 11815879. The next prime is 11815939. The reversal of 11815897 is 79851811.

11815897 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 4734976 + 7080921 = 2176^2 + 2661^2 .

It is a cyclic number.

It is not a de Polignac number, because 11815897 - 2¹¹ = 11813849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11815877) 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, 247 + ... + 4867.

It is an arithmetic number, because the mean of its divisors is an integer number (2955769).

Almost surely, 2^11815897 is an apocalyptic number.

It is an amenable number.

11815897 is a deficient number, since it is larger than the sum of its proper divisors (7179).

11815897 is an equidigital number, since it uses as much as digits as its factorization.

11815897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7178.

The product of its digits is 20160, while the sum is 40.

The square root of 11815897 is about 3437.4259264746. The cubic root of 11815897 is about 227.7660021057.

The spelling of 11815897 in words is "eleven million, eight hundred fifteen thousand, eight hundred ninety-seven".