211121020000021 has 8 divisors (see below), whose sum is σ = 223548942097944. Its totient is φ = 198694102187520.

The previous prime is 211121020000003. The next prime is 211121020000049. The reversal of 211121020000021 is 120000020121112.

It can be written as a sum of positive squares in 4 ways, for example, as 47211534234225 + 163909485765796 = 6871065^2 + 12802714^2 .

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 211121020000021 - 2²⁹ = 211120483129109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211121019999956 and 211121020000010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211121020000061) 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, 250638520 + ... + 251479441.

It is an arithmetic number, because the mean of its divisors is an integer number (27943617762243).

Almost surely, 2^{211121020000021} is an apocalyptic number.

It is an amenable number.

211121020000021 is a deficient number, since it is larger than the sum of its proper divisors (12427922097923).

211121020000021 is a wasteful number, since it uses less digits than its factorization.

211121020000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502142711.

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

Adding to 211121020000021 its reverse (120000020121112), we get a palindrome (331121040121133).

The spelling of 211121020000021 in words is "two hundred eleven trillion, one hundred twenty-one billion, twenty million, twenty-one", and thus it is an aban number.