1021100221021 has 4 divisors (see below), whose sum is σ = 1056310573500. Its totient is φ = 985889868544.

The previous prime is 1021100221019. The next prime is 1021100221033. The reversal of 1021100221021 is 1201220011201.

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 178396416900 + 842703804121 = 422370^2 + 917989^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021100221021 - 2¹ = 1021100221019 is a prime.

It is a super-2 number, since 2×1021100221021² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021100220992 and 1021100221010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021100221061) 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, 17605176196 + ... + 17605176253.

It is an arithmetic number, because the mean of its divisors is an integer number (264077643375).

Almost surely, 2^{1021100221021} is an apocalyptic number.

It is an amenable number.

1021100221021 is a deficient number, since it is larger than the sum of its proper divisors (35210352479).

1021100221021 is an equidigital number, since it uses as much as digits as its factorization.

1021100221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35210352478.

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

Adding to 1021100221021 its reverse (1201220011201), we get a palindrome (2222320232222).

The spelling of 1021100221021 in words is "one trillion, twenty-one billion, one hundred million, two hundred twenty-one thousand, twenty-one".