221100221001021 has 4 divisors (see below), whose sum is σ = 294800294668032. Its totient is φ = 147400147334012.

The previous prime is 221100221001007. The next prime is 221100221001097. The reversal of 221100221001021 is 120100122001122.

221100221001021 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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 221100221001021 - 2¹³ = 221100220992829 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221100221001001) 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, 36850036833501 + ... + 36850036833506.

It is an arithmetic number, because the mean of its divisors is an integer number (73700073667008).

Almost surely, 2^{221100221001021} is an apocalyptic number.

It is an amenable number.

221100221001021 is a deficient number, since it is larger than the sum of its proper divisors (73700073667011).

221100221001021 is an equidigital number, since it uses as much as digits as its factorization.

221100221001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73700073667010.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 221100221001021 its reverse (120100122001122), we get a palindrome (341200343002143).

The spelling of 221100221001021 in words is "two hundred twenty-one trillion, one hundred billion, two hundred twenty-one million, one thousand, twenty-one".