12009813 has 4 divisors (see below), whose sum is σ = 16013088. Its totient is φ = 8006540.

The previous prime is 12009791. The next prime is 12009821. The reversal of 12009813 is 31890021.

12009813 is digitally balanced in base 2, 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 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 12009813 - 2¹² = 12005717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12004813) 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, 2001633 + ... + 2001638.

It is an arithmetic number, because the mean of its divisors is an integer number (4003272).

Almost surely, 2^12009813 is an apocalyptic number.

It is an amenable number.

12009813 is a deficient number, since it is larger than the sum of its proper divisors (4003275).

12009813 is an equidigital number, since it uses as much as digits as its factorization.

12009813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4003274.

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 12009813 is about 3465.5177102419. The cubic root of 12009813 is about 229.0052375123.

Adding to 12009813 its reverse (31890021), we get a palindrome (43899834).

The spelling of 12009813 in words is "twelve million, nine thousand, eight hundred thirteen".