21000112020121 has 64 divisors (see below), whose sum is σ = 23844345348096. Its totient is φ = 18362121465600.

The previous prime is 21000112020119. The next prime is 21000112020131. The reversal of 21000112020121 is 12102021100012.

It is a cyclic number.

It is not a de Polignac number, because 21000112020121 - 2¹ = 21000112020119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is not an unprimeable number, because it can be changed into a prime (21000112020131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2864559426 + ... + 2864566756.

It is an arithmetic number, because the mean of its divisors is an integer number (372567896064).

Almost surely, 2^{21000112020121} is an apocalyptic number.

It is an amenable number.

21000112020121 is a deficient number, since it is larger than the sum of its proper divisors (2844233327975).

21000112020121 is a wasteful number, since it uses less digits than its factorization.

21000112020121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8102.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21000112020121 its reverse (12102021100012), we get a palindrome (33102133120133).

The spelling of 21000112020121 in words is "twenty-one trillion, one hundred twelve million, twenty thousand, one hundred twenty-one".