221001020021021 has 16 divisors (see below), whose sum is σ = 223033879468800. Its totient is φ = 218978530817088.

The previous prime is 221001020020967. The next prime is 221001020021051. The reversal of 221001020021021 is 120120020100122.

It is a cyclic number.

It is not a de Polignac number, because 221001020021021 - 2¹⁸ = 221001019758877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221001020020987 and 221001020021005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221001020021051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 91526591 + ... + 93910163.

It is an arithmetic number, because the mean of its divisors is an integer number (13939617466800).

Almost surely, 2^{221001020021021} is an apocalyptic number.

It is an amenable number.

221001020021021 is a deficient number, since it is larger than the sum of its proper divisors (2032859447779).

221001020021021 is a wasteful number, since it uses less digits than its factorization.

221001020021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2385748.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 221001020021021 its reverse (120120020100122), we get a palindrome (341121040121143).

The spelling of 221001020021021 in words is "two hundred twenty-one trillion, one billion, twenty million, twenty-one thousand, twenty-one".