1220540225 has 12 divisors (see below), whose sum is σ = 1513953324. Its totient is φ = 976120320.

The previous prime is 1220540179. The next prime is 1220540291. The reversal of 1220540225 is 5220450221.

It can be written as a sum of positive squares in 6 ways, for example, as 98089216 + 1122451009 = 9904^2 + 33503^2 .

It is not a de Polignac number, because 1220540225 - 2⁶ = 1220540161 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 1220540225.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 102797 + ... + 114053.

It is an arithmetic number, because the mean of its divisors is an integer number (126162777).

Almost surely, 2^1220540225 is an apocalyptic number.

It is an amenable number.

1220540225 is a deficient number, since it is larger than the sum of its proper divisors (293413099).

1220540225 is a wasteful number, since it uses less digits than its factorization.

1220540225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15604 (or 15599 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 1220540225 is about 34936.2308356239. The cubic root of 1220540225 is about 1068.6874244908.

Adding to 1220540225 its reverse (5220450221), we get a palindrome (6440990446).

The spelling of 1220540225 in words is "one billion, two hundred twenty million, five hundred forty thousand, two hundred twenty-five".