21201122120 has 32 divisors (see below), whose sum is σ = 47709372600. Its totient is φ = 8479231488.

The previous prime is 21201122113. The next prime is 21201122123. The reversal of 21201122120 is 2122110212.

It can be written as a sum of positive squares in 4 ways, for example, as 21201107236 + 14884 = 145606^2 + 122^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21201122095 and 21201122104.

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, 276116 + ... + 344444.

Almost surely, 2^21201122120 is an apocalyptic number.

21201122120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201122120 is an abundant number, since it is smaller than the sum of its proper divisors (26508250480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21201122120 is a wasteful number, since it uses less digits than its factorization.

21201122120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76097 (or 76093 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21201122120 its reverse (2122110212), we get a palindrome (23323232332).

The spelling of 21201122120 in words is "twenty-one billion, two hundred one million, one hundred twenty-two thousand, one hundred twenty".