8380021 has 4 divisors (see below), whose sum is σ = 9024652. Its totient is φ = 7735392.

The previous prime is 8379961. The next prime is 8380037. The reversal of 8380021 is 1200838.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3478225 + 4901796 = 1865^2 + 2214^2 .

It is a cyclic number.

It is not a de Polignac number, because 8380021 - 2¹¹ = 8377973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 8379974 and 8380001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8380051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 322296 + ... + 322321.

It is an arithmetic number, because the mean of its divisors is an integer number (2256163).

Almost surely, 2^8380021 is an apocalyptic number.

It is an amenable number.

8380021 is a deficient number, since it is larger than the sum of its proper divisors (644631).

8380021 is a wasteful number, since it uses less digits than its factorization.

8380021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 644630.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 8380021 is about 2894.8265923886. The cubic root of 8380021 is about 203.1179800651.

Adding to 8380021 its reverse (1200838), we get a palindrome (9580859).

The spelling of 8380021 in words is "eight million, three hundred eighty thousand, twenty-one".