221221210009 has 4 divisors (see below), whose sum is σ = 221270124816. Its totient is φ = 221172295204.

The previous prime is 221221209991. The next prime is 221221210057. The reversal of 221221210009 is 900012122122.

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 221221210009 - 2⁹ = 221221209497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221221213009) 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, 24450619 + ... + 24459664.

It is an arithmetic number, because the mean of its divisors is an integer number (55317531204).

Almost surely, 2^221221210009 is an apocalyptic number.

It is an amenable number.

221221210009 is a deficient number, since it is larger than the sum of its proper divisors (48914807).

221221210009 is an equidigital number, since it uses as much as digits as its factorization.

221221210009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48914806.

The product of its (nonzero) digits is 288, while the sum is 22.

The spelling of 221221210009 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred ten thousand, nine".