221105601 has 18 divisors (see below), whose sum is σ = 333871538. Its totient is φ = 140991840.

The previous prime is 221105597. The next prime is 221105617. The reversal of 221105601 is 106501122.

It can be written as a sum of positive squares in only one way, i.e., 152547201 + 68558400 = 12351^2 + 8280^2 .

It is not a de Polignac number, because 221105601 - 2² = 221105597 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221105681) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 18460 + ... + 27981.

Almost surely, 2^221105601 is an apocalyptic number.

It is an amenable number.

221105601 is a deficient number, since it is larger than the sum of its proper divisors (112765937).

221105601 is a wasteful number, since it uses less digits than its factorization.

221105601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46493 (or 46467 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 221105601 is about 14869.6200691208. The cubic root of 221105601 is about 604.6906425612.

Adding to 221105601 its reverse (106501122), we get a palindrome (327606723).

The spelling of 221105601 in words is "two hundred twenty-one million, one hundred five thousand, six hundred one".