21002100121121 has 8 divisors (see below), whose sum is σ = 24012430412544. Its totient is φ = 17994277398240.

The previous prime is 21002100121081. The next prime is 21002100121127. The reversal of 21002100121121 is 12112100120012.

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 21002100121121 - 2³⁸ = 20727222214177 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21002100121096 and 21002100121105.

It is not an unprimeable number, because it can be changed into a prime (21002100121127) 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, 626874185 + ... + 626907686.

It is an arithmetic number, because the mean of its divisors is an integer number (3001553801568).

Almost surely, 2^{21002100121121} is an apocalyptic number.

It is an amenable number.

21002100121121 is a deficient number, since it is larger than the sum of its proper divisors (3010330291423).

21002100121121 is a wasteful number, since it uses less digits than its factorization.

21002100121121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1253784271.

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

Adding to 21002100121121 its reverse (12112100120012), we get a palindrome (33114200241133).

The spelling of 21002100121121 in words is "twenty-one trillion, two billion, one hundred million, one hundred twenty-one thousand, one hundred twenty-one".