221120212100021 has 8 divisors (see below), whose sum is σ = 239151474034200. Its totient is φ = 203234952287232.

The previous prime is 221120212100009. The next prime is 221120212100089. The reversal of 221120212100021 is 120001212021122.

It can be written as a sum of positive squares in 4 ways, for example, as 2870144222500 + 218250067877521 = 1694150^2 + 14773289^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221120212100021 - 2¹⁴ = 221120212083637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221120212100321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36500527196 + ... + 36500533253.

It is an arithmetic number, because the mean of its divisors is an integer number (29893934254275).

Almost surely, 2^{221120212100021} is an apocalyptic number.

It is an amenable number.

221120212100021 is a deficient number, since it is larger than the sum of its proper divisors (18031261934179).

221120212100021 is a wasteful number, since it uses less digits than its factorization.

221120212100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73001060695.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 221120212100021 its reverse (120001212021122), we get a palindrome (341121424121143).

The spelling of 221120212100021 in words is "two hundred twenty-one trillion, one hundred twenty billion, two hundred twelve million, one hundred thousand, twenty-one".