221001220209 has 32 divisors (see below), whose sum is σ = 388989167616. Its totient is φ = 108052542720.

The previous prime is 221001220201. The next prime is 221001220213. The reversal of 221001220209 is 902022100122.

It is a happy number.

It is not a de Polignac number, because 221001220209 - 2³ = 221001220201 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (221001220201) 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 31 ways as a sum of consecutive naturals, for example, 28134757 + ... + 28142610.

It is an arithmetic number, because the mean of its divisors is an integer number (12155911488).

Almost surely, 2^221001220209 is an apocalyptic number.

It is an amenable number.

221001220209 is a deficient number, since it is larger than the sum of its proper divisors (167987947407).

221001220209 is a wasteful number, since it uses less digits than its factorization.

221001220209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56277405.

The product of its (nonzero) digits is 288, while the sum is 21.

The spelling of 221001220209 in words is "two hundred twenty-one billion, one million, two hundred twenty thousand, two hundred nine".