21121121110101 has 16 divisors (see below), whose sum is σ = 28524086722560. Its totient is φ = 13899527918640.

The previous prime is 21121121110007. The next prime is 21121121110151. The reversal of 21121121110101 is 10101112112112.

It is not a de Polignac number, because 21121121110101 - 2¹³ = 21121121101909 is a prime.

It is a super-2 number, since 2×21121121110101² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121121110151) 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 15 ways as a sum of consecutive naturals, for example, 8450805 + ... + 10661066.

It is an arithmetic number, because the mean of its divisors is an integer number (1782755420160).

Almost surely, 2^{21121121110101} is an apocalyptic number.

It is an amenable number.

21121121110101 is a deficient number, since it is larger than the sum of its proper divisors (7402965612459).

21121121110101 is a wasteful number, since it uses less digits than its factorization.

21121121110101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19116616.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21121121110101 its reverse (10101112112112), we get a palindrome (31222233222213).

The spelling of 21121121110101 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty-one million, one hundred ten thousand, one hundred one".