7745221 has 4 divisors (see below), whose sum is σ = 8449344. Its totient is φ = 7041100.

The previous prime is 7745207. The next prime is 7745263. The reversal of 7745221 is 1225477.

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 not a de Polignac number, because 7745221 - 2⁵ = 7745189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7745221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7740221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 352045 + ... + 352066.

It is an arithmetic number, because the mean of its divisors is an integer number (2112336).

Almost surely, 2^7745221 is an apocalyptic number.

It is an amenable number.

7745221 is a deficient number, since it is larger than the sum of its proper divisors (704123).

7745221 is a wasteful number, since it uses less digits than its factorization.

7745221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704122.

The product of its digits is 3920, while the sum is 28.

The square root of 7745221 is about 2783.0237153140. The cubic root of 7745221 is about 197.8538952082.

It can be divided in two parts, 774 and 5221, that added together give a palindrome (5995).

The spelling of 7745221 in words is "seven million, seven hundred forty-five thousand, two hundred twenty-one".