8747221 has 4 divisors (see below), whose sum is σ = 9996832. Its totient is φ = 7497612.

The previous prime is 8747213. The next prime is 8747243. The reversal of 8747221 is 1227478.

8747221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8747221 - 2³ = 8747213 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 (8747251) 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, 624795 + ... + 624808.

It is an arithmetic number, because the mean of its divisors is an integer number (2499208).

Almost surely, 2^8747221 is an apocalyptic number.

It is an amenable number.

8747221 is a deficient number, since it is larger than the sum of its proper divisors (1249611).

8747221 is a wasteful number, since it uses less digits than its factorization.

8747221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1249610.

The product of its digits is 6272, while the sum is 31.

The square root of 8747221 is about 2957.5701175120. The cubic root of 8747221 is about 206.0424473436.

The spelling of 8747221 in words is "eight million, seven hundred forty-seven thousand, two hundred twenty-one".