21112001021121 has 8 divisors (see below), whose sum is σ = 28149385340160. Its totient is φ = 14074642024752.

The previous prime is 21112001021099. The next prime is 21112001021123. The reversal of 21112001021121 is 12112010021112.

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 21112001021121 - 2²³ = 21111992632513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21112001021121.

It is not an unprimeable number, because it can be changed into a prime (21112001021123) 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, 4291486 + ... + 7787223.

It is an arithmetic number, because the mean of its divisors is an integer number (3518673167520).

Almost surely, 2^{21112001021121} is an apocalyptic number.

It is an amenable number.

21112001021121 is a deficient number, since it is larger than the sum of its proper divisors (7037384319039).

21112001021121 is a wasteful number, since it uses less digits than its factorization.

21112001021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12661335.

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

Adding to 21112001021121 its reverse (12112010021112), we get a palindrome (33224011042233).

The spelling of 21112001021121 in words is "twenty-one trillion, one hundred twelve billion, one million, twenty-one thousand, one hundred twenty-one".