909221 has 4 divisors (see below), whose sum is σ = 912000. Its totient is φ = 906444.

The previous prime is 909217. The next prime is 909239. The reversal of 909221 is 122909.

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, and also an emirpimes, since its reverse is a distinct semiprime: 122909 = 89 ⋅1381.

It is a cyclic number.

It is not a de Polignac number, because 909221 - 2² = 909217 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 (909241) 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, 821 + ... + 1578.

It is an arithmetic number, because the mean of its divisors is an integer number (228000).

2⁹⁰⁹²²¹ is an apocalyptic number.

It is an amenable number.

909221 is a deficient number, since it is larger than the sum of its proper divisors (2779).

909221 is a wasteful number, since it uses less digits than its factorization.

909221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2778.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 909221 is about 953.5308070534. The cubic root of 909221 is about 96.8775512335.

The spelling of 909221 in words is "nine hundred nine thousand, two hundred twenty-one".