7221121 has 4 divisors (see below), whose sum is σ = 7601200. Its totient is φ = 6841044.

The previous prime is 7221101. The next prime is 7221131. The reversal of 7221121 is 1211227.

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 7221121 - 2⁵ = 7221089 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7221095 and 7221104.

It is not an unprimeable number, because it can be changed into a prime (7221101) 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, 190011 + ... + 190048.

It is an arithmetic number, because the mean of its divisors is an integer number (1900300).

Almost surely, 2^7221121 is an apocalyptic number.

It is an amenable number.

7221121 is a deficient number, since it is larger than the sum of its proper divisors (380079).

7221121 is a wasteful number, since it uses less digits than its factorization.

7221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380078.

The product of its digits is 56, while the sum is 16.

The square root of 7221121 is about 2687.2143569131. The cubic root of 7221121 is about 193.2865083455.

Adding to 7221121 its reverse (1211227), we get a palindrome (8432348).

The spelling of 7221121 in words is "seven million, two hundred twenty-one thousand, one hundred twenty-one".