21010120021121 has 16 divisors (see below), whose sum is σ = 26208741608448. Its totient is φ = 16362580683600.

The previous prime is 21010120021073. The next prime is 21010120021129. The reversal of 21010120021121 is 12112002101012.

It is a cyclic number.

It is not a de Polignac number, because 21010120021121 - 2⁶ = 21010120021057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21010120021096 and 21010120021105.

It is not an unprimeable number, because it can be changed into a prime (21010120021129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74369855 + ... + 74651828.

It is an arithmetic number, because the mean of its divisors is an integer number (1638046350528).

Almost surely, 2^{21010120021121} is an apocalyptic number.

It is an amenable number.

21010120021121 is a deficient number, since it is larger than the sum of its proper divisors (5198621587327).

21010120021121 is a wasteful number, since it uses less digits than its factorization.

21010120021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149023532.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21010120021121 its reverse (12112002101012), we get a palindrome (33122122122133).

The spelling of 21010120021121 in words is "twenty-one trillion, ten billion, one hundred twenty million, twenty-one thousand, one hundred twenty-one".