8117521 has 2 divisors, whose sum is σ = 8117522. Its totient is φ = 8117520.

The previous prime is 8117513. The next prime is 8117537. The reversal of 8117521 is 1257118.

8117521 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8059921 + 57600 = 2839^2 + 240^2 .

It is a cyclic number.

It is not a de Polignac number, because 8117521 - 2³ = 8117513 is a prime.

It is not a weakly prime, because it can be changed into another prime (8117561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4058760 + 4058761.

It is an arithmetic number, because the mean of its divisors is an integer number (4058761).

Almost surely, 2^8117521 is an apocalyptic number.

It is an amenable number.

8117521 is a deficient number, since it is larger than the sum of its proper divisors (1).

8117521 is an equidigital number, since it uses as much as digits as its factorization.

8117521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 560, while the sum is 25.

The square root of 8117521 is about 2849.1263573243. The cubic root of 8117521 is about 200.9745848743.

The spelling of 8117521 in words is "eight million, one hundred seventeen thousand, five hundred twenty-one".