1021221220111 has 4 divisors (see below), whose sum is σ = 1074969705400. Its totient is φ = 967472734824.

The previous prime is 1021221220087. The next prime is 1021221220133. The reversal of 1021221220111 is 1110221221201.

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 1021221220111 - 2¹³ = 1021221211919 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 (1021221220141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26874242616 + ... + 26874242653.

It is an arithmetic number, because the mean of its divisors is an integer number (268742426350).

Almost surely, 2^{1021221220111} is an apocalyptic number.

1021221220111 is a deficient number, since it is larger than the sum of its proper divisors (53748485289).

1021221220111 is an equidigital number, since it uses as much as digits as its factorization.

1021221220111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53748485288.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1021221220111 its reverse (1110221221201), we get a palindrome (2131442441312).

The spelling of 1021221220111 in words is "one trillion, twenty-one billion, two hundred twenty-one million, two hundred twenty thousand, one hundred eleven".