21020221111121 has 8 divisors (see below), whose sum is σ = 21040982061120. Its totient is φ = 20999462214672.

The previous prime is 21020221111117. The next prime is 21020221111171. The reversal of 21020221111121 is 12111112202012.

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 21020221111121 - 2² = 21020221111117 is a prime.

It is a super-3 number, since 3×21020221111121³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21020221111121.

It is not an unprimeable number, because it can be changed into a prime (21020221111171) 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, 20388386 + ... + 21394548.

It is an arithmetic number, because the mean of its divisors is an integer number (2630122757640).

Almost surely, 2^{21020221111121} is an apocalyptic number.

It is an amenable number.

21020221111121 is a deficient number, since it is larger than the sum of its proper divisors (20760949999).

21020221111121 is a wasteful number, since it uses less digits than its factorization.

21020221111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1026775.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21020221111121 its reverse (12111112202012), we get a palindrome (33131333313133).

The spelling of 21020221111121 in words is "twenty-one trillion, twenty billion, two hundred twenty-one million, one hundred eleven thousand, one hundred twenty-one".