8147421 has 6 divisors (see below), whose sum is σ = 11768510. Its totient is φ = 5431608.

The previous prime is 8147417. The next prime is 8147443. The reversal of 8147421 is 1247418.

8147421 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 4575321 + 3572100 = 2139^2 + 1890^2 .

It is not a de Polignac number, because 8147421 - 2² = 8147417 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 (8147621) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 452626 + ... + 452643.

Almost surely, 2^8147421 is an apocalyptic number.

It is an amenable number.

8147421 is a deficient number, since it is larger than the sum of its proper divisors (3621089).

8147421 is a wasteful number, since it uses less digits than its factorization.

8147421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905275 (or 905272 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 8147421 is about 2854.3687568357. The cubic root of 8147421 is about 201.2210384877.

The spelling of 8147421 in words is "eight million, one hundred forty-seven thousand, four hundred twenty-one".