8115421 has 2 divisors, whose sum is σ = 8115422. Its totient is φ = 8115420.

The previous prime is 8115407. The next prime is 8115431. The reversal of 8115421 is 1245118.

8115421 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6687396 + 1428025 = 2586^2 + 1195^2 .

It is a cyclic number.

It is not a de Polignac number, because 8115421 - 2⁷ = 8115293 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 8115392 and 8115401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8115431) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4057710 + 4057711.

It is an arithmetic number, because the mean of its divisors is an integer number (4057711).

Almost surely, 2^8115421 is an apocalyptic number.

It is an amenable number.

8115421 is a deficient number, since it is larger than the sum of its proper divisors (1).

8115421 is an equidigital number, since it uses as much as digits as its factorization.

8115421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 320, while the sum is 22.

The square root of 8115421 is about 2848.7577994628. The cubic root of 8115421 is about 200.9572526934.

The spelling of 8115421 in words is "eight million, one hundred fifteen thousand, four hundred twenty-one".