21000010111121 has 24 divisors (see below), whose sum is σ = 22448187158400. Its totient is φ = 19639245731040.

The previous prime is 21000010111063. The next prime is 21000010111153. The reversal of 21000010111121 is 12111101000012.

It is not a de Polignac number, because 21000010111121 - 2¹⁰ = 21000010110097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000010111321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 159098570 + ... + 159230508.

It is an arithmetic number, because the mean of its divisors is an integer number (935341131600).

Almost surely, 2^{21000010111121} is an apocalyptic number.

It is an amenable number.

21000010111121 is a deficient number, since it is larger than the sum of its proper divisors (1448177047279).

21000010111121 is a wasteful number, since it uses less digits than its factorization.

21000010111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137637 (or 137618 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21000010111121 its reverse (12111101000012), we get a palindrome (33111111111133).

The spelling of 21000010111121 in words is "twenty-one trillion, ten million, one hundred eleven thousand, one hundred twenty-one".