8450221 has 4 divisors (see below), whose sum is σ = 9100252. Its totient is φ = 7800192.

The previous prime is 8450209. The next prime is 8450243. The reversal of 8450221 is 1220548.

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 4247721 + 4202500 = 2061^2 + 2050^2 .

It is a cyclic number.

It is not a de Polignac number, because 8450221 - 2⁹ = 8449709 is a prime.

It is a Duffinian number.

8450221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 8450192 and 8450201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8450201) 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, 324996 + ... + 325021.

It is an arithmetic number, because the mean of its divisors is an integer number (2275063).

Almost surely, 2^8450221 is an apocalyptic number.

It is an amenable number.

8450221 is a deficient number, since it is larger than the sum of its proper divisors (650031).

8450221 is a wasteful number, since it uses less digits than its factorization.

8450221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650030.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 8450221 is about 2906.9263836568. The cubic root of 8450221 is about 203.6835812969.

Adding to 8450221 its reverse (1220548), we get a palindrome (9670769).

It can be divided in two parts, 84 and 50221, that added together give a palindrome (50305).

The spelling of 8450221 in words is "eight million, four hundred fifty thousand, two hundred twenty-one".