8651221 has 8 divisors (see below), whose sum is σ = 8808800. Its totient is φ = 8495280.

The previous prime is 8651207. The next prime is 8651231. The reversal of 8651221 is 1221568.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8651221 - 2⁵ = 8651189 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8651231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14866 + ... + 15436.

It is an arithmetic number, because the mean of its divisors is an integer number (1101100).

Almost surely, 2^8651221 is an apocalyptic number.

It is an amenable number.

8651221 is a deficient number, since it is larger than the sum of its proper divisors (157579).

8651221 is a wasteful number, since it uses less digits than its factorization.

8651221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 819.

The product of its digits is 960, while the sum is 25.

The square root of 8651221 is about 2941.2958028733. The cubic root of 8651221 is about 205.2859068400.

Adding to 8651221 its reverse (1221568), we get a palindrome (9872789).

The spelling of 8651221 in words is "eight million, six hundred fifty-one thousand, two hundred twenty-one".