221120101021 has 4 divisors (see below), whose sum is σ = 221776244092. Its totient is φ = 220463957952.

The previous prime is 221120101003. The next prime is 221120101043. The reversal of 221120101021 is 120101021122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120101021122 = 2 ⋅60050510561.

It can be written as a sum of positive squares in 2 ways, for example, as 165429292900 + 55690808121 = 406730^2 + 235989^2 .

It is a cyclic number.

It is not a de Polignac number, because 221120101021 - 2¹⁷ = 221119969949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221120100992 and 221120101010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221120101421) 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, 328071030 + ... + 328071703.

It is an arithmetic number, because the mean of its divisors is an integer number (55444061023).

Almost surely, 2^221120101021 is an apocalyptic number.

It is an amenable number.

221120101021 is a deficient number, since it is larger than the sum of its proper divisors (656143071).

221120101021 is an equidigital number, since it uses as much as digits as its factorization.

221120101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656143070.

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

Adding to 221120101021 its reverse (120101021122), we get a palindrome (341221122143).

The spelling of 221120101021 in words is "two hundred twenty-one billion, one hundred twenty million, one hundred one thousand, twenty-one".