221011122120021 has 6 divisors (see below), whose sum is σ = 319238287506710. Its totient is φ = 147340748080008.

The previous prime is 221011122119987. The next prime is 221011122120023. The reversal of 221011122120021 is 120021221110122.

221011122120021 is a `hidden beast` number, since 2 + 210 + 1 + 11 + 221 + 200 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 208518509628900 + 12492612491121 = 14440170^2 + 3534489^2 .

It is not a de Polignac number, because 221011122120021 - 2¹⁵ = 221011122087253 is a prime.

It is a super-2 number, since 2×221011122120021² (a number of 29 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 = 221011122119976 and 221011122120003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221011122120023) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12278395673326 + ... + 12278395673343.

Almost surely, 2^{221011122120021} is an apocalyptic number.

It is an amenable number.

221011122120021 is a deficient number, since it is larger than the sum of its proper divisors (98227165386689).

221011122120021 is a wasteful number, since it uses less digits than its factorization.

221011122120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24556791346675 (or 24556791346672 counting only the distinct ones).

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

Adding to 221011122120021 its reverse (120021221110122), we get a palindrome (341032343230143).

The spelling of 221011122120021 in words is "two hundred twenty-one trillion, eleven billion, one hundred twenty-two million, one hundred twenty thousand, twenty-one".