201221221209 has 4 divisors (see below), whose sum is σ = 268294961616. Its totient is φ = 134147480804.

The previous prime is 201221221189. The next prime is 201221221211. The reversal of 201221221209 is 902122122102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 201221221209 - 2¹⁷ = 201221090137 is a prime.

It is a super-2 number, since 2×201221221209² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (201221221009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33536870199 + ... + 33536870204.

It is an arithmetic number, because the mean of its divisors is an integer number (67073740404).

Almost surely, 2^201221221209 is an apocalyptic number.

It is an amenable number.

201221221209 is a deficient number, since it is larger than the sum of its proper divisors (67073740407).

201221221209 is an equidigital number, since it uses as much as digits as its factorization.

201221221209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67073740406.

The product of its (nonzero) digits is 576, while the sum is 24.

The spelling of 201221221209 in words is "two hundred one billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred nine".