221101101111001 has 4 divisors (see below), whose sum is σ = 221133803543604. Its totient is φ = 221068398678400.

The previous prime is 221101101110993. The next prime is 221101101111029. The reversal of 221101101111001 is 100111101101122.

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 69249109776025 + 151851991334976 = 8321605^2 + 12322824^2 .

It is a cyclic number.

It is not a de Polignac number, because 221101101111001 - 2³ = 221101101110993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221101101111041) 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, 16351206160 + ... + 16351219681.

It is an arithmetic number, because the mean of its divisors is an integer number (55283450885901).

Almost surely, 2^{221101101111001} is an apocalyptic number.

It is an amenable number.

221101101111001 is a deficient number, since it is larger than the sum of its proper divisors (32702432603).

221101101111001 is an equidigital number, since it uses as much as digits as its factorization.

221101101111001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32702432602.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 221101101111001 its reverse (100111101101122), we get a palindrome (321212202212123).

The spelling of 221101101111001 in words is "two hundred twenty-one trillion, one hundred one billion, one hundred one million, one hundred eleven thousand, one".