7720225 has 6 divisors (see below), whose sum is σ = 9573110. Its totient is φ = 6176160.

The previous prime is 7720211. The next prime is 7720241. The reversal of 7720225 is 5220277.

It can be written as a sum of positive squares in 3 ways, for example, as 2411809 + 5308416 = 1553^2 + 2304^2 .

It is not a de Polignac number, because 7720225 - 2¹¹ = 7718177 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 308809 = 7720225 / (7 + 7 + 2 + 0 + 2 + 2 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 7720225.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 154380 + ... + 154429.

Almost surely, 2^7720225 is an apocalyptic number.

It is an amenable number.

7720225 is a deficient number, since it is larger than the sum of its proper divisors (1852885).

7720225 is a wasteful number, since it uses less digits than its factorization.

7720225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308819 (or 308814 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 25.

The square root of 7720225 is about 2778.5292872309. The cubic root of 7720225 is about 197.6408224952.

It can be divided in two parts, 77 and 20225, that added together give a palindrome (20302).

The spelling of 7720225 in words is "seven million, seven hundred twenty thousand, two hundred twenty-five".