21011010120121 has 16 divisors (see below), whose sum is σ = 24840807373440. Its totient is φ = 17388279175680.

The previous prime is 21011010120091. The next prime is 21011010120127. The reversal of 21011010120121 is 12102101011012.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-21011010120121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011010120127) 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, 29486281 + ... + 30190441.

It is an arithmetic number, because the mean of its divisors is an integer number (1552550460840).

Almost surely, 2^{21011010120121} is an apocalyptic number.

It is an amenable number.

21011010120121 is a deficient number, since it is larger than the sum of its proper divisors (3829797253319).

21011010120121 is a wasteful number, since it uses less digits than its factorization.

21011010120121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 851184.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21011010120121 its reverse (12102101011012), we get a palindrome (33113111131133).

The spelling of 21011010120121 in words is "twenty-one trillion, eleven billion, ten million, one hundred twenty thousand, one hundred twenty-one".