6813520091 has 4 divisors (see below), whose sum is σ = 7786880112. Its totient is φ = 5840160072.

The previous prime is 6813520073. The next prime is 6813520199. The reversal of 6813520091 is 1900253186.

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 6813520091 - 2⁶ = 6813520027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6813520001) 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, 486680000 + ... + 486680013.

It is an arithmetic number, because the mean of its divisors is an integer number (1946720028).

Almost surely, 2^6813520091 is an apocalyptic number.

6813520091 is a deficient number, since it is larger than the sum of its proper divisors (973360021).

6813520091 is an equidigital number, since it uses as much as digits as its factorization.

6813520091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 973360020.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 6813520091 is about 82544.0493978821. The cubic root of 6813520091 is about 1895.7912463519.

The spelling of 6813520091 in words is "six billion, eight hundred thirteen million, five hundred twenty thousand, ninety-one".