7221329 has 4 divisors (see below), whose sum is σ = 7229040. Its totient is φ = 7213620.

The previous prime is 7221307. The next prime is 7221353. The reversal of 7221329 is 9231227.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9231227 = 233 ⋅39619.

It is a cyclic number.

It is not a de Polignac number, because 7221329 - 2²⁰ = 6172753 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7221298 and 7221307.

It is not an unprimeable number, because it can be changed into a prime (7221629) 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, 2219 + ... + 4400.

It is an arithmetic number, because the mean of its divisors is an integer number (1807260).

Almost surely, 2^7221329 is an apocalyptic number.

It is an amenable number.

7221329 is a deficient number, since it is larger than the sum of its proper divisors (7711).

7221329 is a wasteful number, since it uses less digits than its factorization.

7221329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7710.

The product of its digits is 1512, while the sum is 26.

The square root of 7221329 is about 2687.2530584223. The cubic root of 7221329 is about 193.2883641612.

The spelling of 7221329 in words is "seven million, two hundred twenty-one thousand, three hundred twenty-nine".