8394021 has 18 divisors (see below), whose sum is σ = 12568530. Its totient is φ = 5398176.

The previous prime is 8394017. The next prime is 8394037. The reversal of 8394021 is 1204938.

It can be written as a sum of positive squares in 3 ways, for example, as 65025 + 8328996 = 255^2 + 2886^2 .

It is not a de Polignac number, because 8394021 - 2² = 8394017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8394041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 7015 + ... + 8123.

Almost surely, 2^8394021 is an apocalyptic number.

It is an amenable number.

8394021 is a deficient number, since it is larger than the sum of its proper divisors (4174509).

8394021 is a wasteful number, since it uses less digits than its factorization.

8394021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1173 (or 1141 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 8394021 is about 2897.2436901303. The cubic root of 8394021 is about 203.2310294881.

Adding to 8394021 its reverse (1204938), we get a palindrome (9598959).

The spelling of 8394021 in words is "eight million, three hundred ninety-four thousand, twenty-one".