8271197821 has 2 divisors, whose sum is σ = 8271197822. Its totient is φ = 8271197820.

The previous prime is 8271197807. The next prime is 8271197863. The reversal of 8271197821 is 1287911728.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5635504900 + 2635692921 = 75070^2 + 51339^2 .

It is a cyclic number.

It is not a de Polignac number, because 8271197821 - 2¹³ = 8271189629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8271197321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4135598910 + 4135598911.

It is an arithmetic number, because the mean of its divisors is an integer number (4135598911).

Almost surely, 2^8271197821 is an apocalyptic number.

It is an amenable number.

8271197821 is a deficient number, since it is larger than the sum of its proper divisors (1).

8271197821 is an equidigital number, since it uses as much as digits as its factorization.

8271197821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 46.

The square root of 8271197821 is about 90946.1259262867. The cubic root of 8271197821 is about 2022.3491459992.

The spelling of 8271197821 in words is "eight billion, two hundred seventy-one million, one hundred ninety-seven thousand, eight hundred twenty-one".