221101221001 has 4 divisors (see below), whose sum is σ = 221103751572. Its totient is φ = 221098690432.

The previous prime is 221101220983. The next prime is 221101221017. The reversal of 221101221001 is 100122101122.

221101221001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 109113944976 + 111987276025 = 330324^2 + 334645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221101221001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221101221031) 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, 1129360 + ... + 1310593.

It is an arithmetic number, because the mean of its divisors is an integer number (55275937893).

Almost surely, 2^221101221001 is an apocalyptic number.

It is an amenable number.

221101221001 is a deficient number, since it is larger than the sum of its proper divisors (2530571).

221101221001 is an equidigital number, since it uses as much as digits as its factorization.

221101221001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2530570.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 221101221001 its reverse (100122101122), we get a palindrome (321223322123).

The spelling of 221101221001 in words is "two hundred twenty-one billion, one hundred one million, two hundred twenty-one thousand, one".