8191000133 has 4 divisors (see below), whose sum is σ = 8193110220. Its totient is φ = 8188890048.

The previous prime is 8191000117. The next prime is 8191000183. The reversal of 8191000133 is 3310001918.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5987354884 + 2203645249 = 77378^2 + 46943^2 .

It is a cyclic number.

It is not a de Polignac number, because 8191000133 - 2⁴ = 8191000117 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 (8191000183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1049210 + ... + 1056987.

It is an arithmetic number, because the mean of its divisors is an integer number (2048277555).

Almost surely, 2^8191000133 is an apocalyptic number.

8191000133 is the 48377-th centered heptagonal number.

It is an amenable number.

8191000133 is a deficient number, since it is larger than the sum of its proper divisors (2110087).

8191000133 is a wasteful number, since it uses less digits than its factorization.

8191000133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2110086.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 8191000133 is about 90504.1442863254. The cubic root of 8191000133 is about 2015.7916612943.

The spelling of 8191000133 in words is "eight billion, one hundred ninety-one million, one hundred thirty-three", and thus it is an aban number.