21000120121011 has 8 divisors (see below), whose sum is σ = 28000709915904. Its totient is φ = 13999805203400.

The previous prime is 21000120120887. The next prime is 21000120121039. The reversal of 21000120121011 is 11012102100012.

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 21000120121011 - 2¹¹ = 21000120118963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000120161011) 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, 68540991 + ... + 68846696.

It is an arithmetic number, because the mean of its divisors is an integer number (3500088739488).

Almost surely, 2^{21000120121011} is an apocalyptic number.

21000120121011 is a deficient number, since it is larger than the sum of its proper divisors (7000589794893).

21000120121011 is a wasteful number, since it uses less digits than its factorization.

21000120121011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137438641.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21000120121011 its reverse (11012102100012), we get a palindrome (32012222221023).

The spelling of 21000120121011 in words is "twenty-one trillion, one hundred twenty million, one hundred twenty-one thousand, eleven".