21201122122 has 16 divisors (see below), whose sum is σ = 31939935552. Its totient is φ = 10554508000.

The previous prime is 21201122113. The next prime is 21201122123. The reversal of 21201122122 is 22122110212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21201122096 and 21201122105.

It is not an unprimeable number, because it can be changed into a prime (21201122123) 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, 1812918 + ... + 1824574.

It is an arithmetic number, because the mean of its divisors is an integer number (1996245972).

Almost surely, 2^21201122122 is an apocalyptic number.

21201122122 is a deficient number, since it is larger than the sum of its proper divisors (10738813430).

21201122122 is a wasteful number, since it uses less digits than its factorization.

21201122122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15533.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21201122122 its reverse (22122110212), we get a palindrome (43323232334).

The spelling of 21201122122 in words is "twenty-one billion, two hundred one million, one hundred twenty-two thousand, one hundred twenty-two".