221021100020111 has 4 divisors (see below), whose sum is σ = 221046264676512. Its totient is φ = 220995935363712.

The previous prime is 221021100020087. The next prime is 221021100020143. The reversal of 221021100020111 is 111020001120122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221021100020111 - 2¹⁴ = 221021100003727 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021100025111) 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, 12582315026 + ... + 12582332591.

It is an arithmetic number, because the mean of its divisors is an integer number (55261566169128).

Almost surely, 2^{221021100020111} is an apocalyptic number.

221021100020111 is a deficient number, since it is larger than the sum of its proper divisors (25164656401).

221021100020111 is an equidigital number, since it uses as much as digits as its factorization.

221021100020111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25164656400.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 221021100020111 its reverse (111020001120122), we get a palindrome (332041101140233).

The spelling of 221021100020111 in words is "two hundred twenty-one trillion, twenty-one billion, one hundred million, twenty thousand, one hundred eleven".