21201122012 has 12 divisors (see below), whose sum is σ = 42402244080. Its totient is φ = 9086195136.

The previous prime is 21201121973. The next prime is 21201122023. The reversal of 21201122012 is 21022110212.

21201122012 is an admirable number.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 378591437 + ... + 378591492.

It is an arithmetic number, because the mean of its divisors is an integer number (3533520340).

Almost surely, 2^21201122012 is an apocalyptic number.

It is an amenable number.

21201122012 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21201122012 is a wasteful number, since it uses less digits than its factorization.

21201122012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 757182940 (or 757182938 counting only the distinct ones).

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

Adding to 21201122012 its reverse (21022110212), we get a palindrome (42223232224).

The spelling of 21201122012 in words is "twenty-one billion, two hundred one million, one hundred twenty-two thousand, twelve".