12195591 has 4 divisors (see below), whose sum is σ = 16260792. Its totient is φ = 8130392.

The previous prime is 12195577. The next prime is 12195593. The reversal of 12195591 is 19559121.

It is a happy number.

12195591 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12195591 - 2⁵ = 12195559 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12195593) 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, 2032596 + ... + 2032601.

It is an arithmetic number, because the mean of its divisors is an integer number (4065198).

Almost surely, 2^12195591 is an apocalyptic number.

12195591 is a deficient number, since it is larger than the sum of its proper divisors (4065201).

12195591 is an equidigital number, since it uses as much as digits as its factorization.

12195591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4065200.

The product of its digits is 4050, while the sum is 33.

The square root of 12195591 is about 3492.2186357672. The cubic root of 12195591 is about 230.1800165976.

It can be divided in two parts, 121 and 95591, that multiplied together give a palindrome (11566511).

The spelling of 12195591 in words is "twelve million, one hundred ninety-five thousand, five hundred ninety-one".