221757201 has 6 divisors (see below), whose sum is σ = 320315970. Its totient is φ = 147838128.

The previous prime is 221757199. The next prime is 221757269. The reversal of 221757201 is 102757122.

It can be written as a sum of positive squares in only one way, i.e., 189778176 + 31979025 = 13776^2 + 5655^2 .

It is not a de Polignac number, because 221757201 - 2¹ = 221757199 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221757271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12319836 + ... + 12319853.

It is an arithmetic number, because the mean of its divisors is an integer number (53385995).

Almost surely, 2^221757201 is an apocalyptic number.

It is an amenable number.

221757201 is a deficient number, since it is larger than the sum of its proper divisors (98558769).

221757201 is a wasteful number, since it uses less digits than its factorization.

221757201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24639695 (or 24639692 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 27.

The square root of 221757201 is about 14891.5143957893. The cubic root of 221757201 is about 605.2840694077.

The spelling of 221757201 in words is "two hundred twenty-one million, seven hundred fifty-seven thousand, two hundred one".