220581561 has 16 divisors (see below), whose sum is σ = 296388288. Its totient is φ = 145920000.

The previous prime is 220581553. The next prime is 220581587. The reversal of 220581561 is 165185022.

It is not a de Polignac number, because 220581561 - 2³ = 220581553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (220581541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 343801 + ... + 344441.

It is an arithmetic number, because the mean of its divisors is an integer number (18524268).

Almost surely, 2^220581561 is an apocalyptic number.

It is an amenable number.

220581561 is a deficient number, since it is larger than the sum of its proper divisors (75806727).

220581561 is a wasteful number, since it uses less digits than its factorization.

220581561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352.

The product of its (nonzero) digits is 4800, while the sum is 30.

The square root of 220581561 is about 14851.9884527291. The cubic root of 220581561 is about 604.2125410578.

The spelling of 220581561 in words is "two hundred twenty million, five hundred eighty-one thousand, five hundred sixty-one".