13720813 has 4 divisors (see below), whose sum is σ = 13886208. Its totient is φ = 13555420.

The previous prime is 13720801. The next prime is 13720823. The reversal of 13720813 is 31802731.

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 13720813 - 2⁵ = 13720781 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 (13720823) 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, 82573 + ... + 82738.

It is an arithmetic number, because the mean of its divisors is an integer number (3471552).

Almost surely, 2^13720813 is an apocalyptic number.

It is an amenable number.

13720813 is a deficient number, since it is larger than the sum of its proper divisors (165395).

13720813 is an equidigital number, since it uses as much as digits as its factorization.

13720813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165394.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 13720813 is about 3704.1615785492. The cubic root of 13720813 is about 239.4013610483.

The spelling of 13720813 in words is "thirteen million, seven hundred twenty thousand, eight hundred thirteen".