2021011111221 has 8 divisors (see below), whose sum is σ = 2694776850240. Its totient is φ = 1347293056512.

The previous prime is 2021011111213. The next prime is 2021011111237. The reversal of 2021011111221 is 1221111101202.

It is a happy number.

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

It is not a de Polignac number, because 2021011111221 - 2³ = 2021011111213 is a prime.

It is a super-3 number, since 3×2021011111221³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 2021011111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021011111271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11822065 + ... + 11991798.

It is an arithmetic number, because the mean of its divisors is an integer number (336847106280).

Almost surely, 2^{2021011111221} is an apocalyptic number.

It is an amenable number.

2021011111221 is a deficient number, since it is larger than the sum of its proper divisors (673765739019).

2021011111221 is a wasteful number, since it uses less digits than its factorization.

2021011111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23842155.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 2021011111221 its reverse (1221111101202), we get a palindrome (3242122212423).

The spelling of 2021011111221 in words is "two trillion, twenty-one billion, eleven million, one hundred eleven thousand, two hundred twenty-one".