13840813 has 4 divisors (see below), whose sum is σ = 15818080. Its totient is φ = 11863548.

The previous prime is 13840807. The next prime is 13840829. The reversal of 13840813 is 31804831.

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 an emirpimes, since its reverse is a distinct semiprime: 31804831 = 271 ⋅117361.

It is a cyclic number.

It is not a de Polignac number, because 13840813 - 2⁵ = 13840781 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 (13840843) 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, 988623 + ... + 988636.

It is an arithmetic number, because the mean of its divisors is an integer number (3954520).

Almost surely, 2^13840813 is an apocalyptic number.

It is an amenable number.

13840813 is a deficient number, since it is larger than the sum of its proper divisors (1977267).

13840813 is an equidigital number, since it uses as much as digits as its factorization.

13840813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1977266.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 13840813 is about 3720.3243138200. The cubic root of 13840813 is about 240.0972580354.

The spelling of 13840813 in words is "thirteen million, eight hundred forty thousand, eight hundred thirteen".