220020561 has 12 divisors (see below), whose sum is σ = 318134388. Its totient is φ = 146529504.

The previous prime is 220020557. The next prime is 220020571. The reversal of 220020561 is 165020022.

It can be written as a sum of positive squares in 2 ways, for example, as 31809600 + 188210961 = 5640^2 + 13719^2 .

It is not a de Polignac number, because 220020561 - 2² = 220020557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (220020571) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2950 + ... + 21183.

It is an arithmetic number, because the mean of its divisors is an integer number (26511199).

Almost surely, 2^220020561 is an apocalyptic number.

It is an amenable number.

220020561 is a deficient number, since it is larger than the sum of its proper divisors (98113827).

220020561 is a wasteful number, since it uses less digits than its factorization.

220020561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25152 (or 25149 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 220020561 is about 14833.0900691663. The cubic root of 220020561 is about 603.6998795887.

Adding to 220020561 its reverse (165020022), we get a palindrome (385040583).

The spelling of 220020561 in words is "two hundred twenty million, twenty thousand, five hundred sixty-one".