221220111120021 has 48 divisors (see below), whose sum is σ = 362269579439040. Its totient is φ = 128956964094720.

The previous prime is 221220111119999. The next prime is 221220111120037. The reversal of 221220111120021 is 120021111022122.

221220111120021 is a `hidden beast` number, since 221 + 220 + 1 + 1 + 1 + 1 + 200 + 21 = 666.

221220111120021 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221220111120021 - 2²⁵ = 221220077565589 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221220111119976 and 221220111120003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221220111120221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 16121841 + ... + 26501961.

It is an arithmetic number, because the mean of its divisors is an integer number (7547282904980).

Almost surely, 2^{221220111120021} is an apocalyptic number.

It is an amenable number.

221220111120021 is a deficient number, since it is larger than the sum of its proper divisors (141049468319019).

221220111120021 is a wasteful number, since it uses less digits than its factorization.

221220111120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10389746 (or 10389743 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 221220111120021 its reverse (120021111022122), we get a palindrome (341241222142143).

The spelling of 221220111120021 in words is "two hundred twenty-one trillion, two hundred twenty billion, one hundred eleven million, one hundred twenty thousand, twenty-one".