201220001 has 4 divisors (see below), whose sum is σ = 203294532. Its totient is φ = 199145472.

The previous prime is 201219917. The next prime is 201220043. The reversal of 201220001 is 100022102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 89283601 + 111936400 = 9449^2 + 10580^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201220001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201222001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1037120 + ... + 1037313.

It is an arithmetic number, because the mean of its divisors is an integer number (50823633).

Almost surely, 2^201220001 is an apocalyptic number.

It is an amenable number.

201220001 is a deficient number, since it is larger than the sum of its proper divisors (2074531).

201220001 is an equidigital number, since it uses as much as digits as its factorization.

201220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2074530.

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 201220001 is about 14185.2035938861. The cubic root of 201220001 is about 585.9902394830.

Adding to 201220001 its reverse (100022102), we get a palindrome (301242103).

The spelling of 201220001 in words is "two hundred one million, two hundred twenty thousand, one".