21000122101 has 32 divisors (see below), whose sum is σ = 25363081728. Its totient is φ = 16998854400.

The previous prime is 21000122093. The next prime is 21000122111. The reversal of 21000122101 is 10122100012.

It is a cyclic number.

It is not a de Polignac number, because 21000122101 - 2³ = 21000122093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000122111) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6453991 + ... + 6457243.

It is an arithmetic number, because the mean of its divisors is an integer number (792596304).

Almost surely, 2^21000122101 is an apocalyptic number.

It is an amenable number.

21000122101 is a deficient number, since it is larger than the sum of its proper divisors (4362959627).

21000122101 is a wasteful number, since it uses less digits than its factorization.

21000122101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3781.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21000122101 its reverse (10122100012), we get a palindrome (31122222113).

The spelling of 21000122101 in words is "twenty-one billion, one hundred twenty-two thousand, one hundred one".