21101022012 has 48 divisors (see below), whose sum is σ = 56293558272. Its totient is φ = 6026274240.

The previous prime is 21101022011. The next prime is 21101022017. The reversal of 21101022012 is 21022010112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101022011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 147253 + ... + 252755.

It is an arithmetic number, because the mean of its divisors is an integer number (1172782464).

Almost surely, 2^21101022012 is an apocalyptic number.

It is an amenable number.

21101022012 is an abundant number, since it is smaller than the sum of its proper divisors (35192536260).

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

21101022012 is a wasteful number, since it uses less digits than its factorization.

21101022012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107898 (or 107896 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21101022012 its reverse (21022010112), we get a palindrome (42123032124).

The spelling of 21101022012 in words is "twenty-one billion, one hundred one million, twenty-two thousand, twelve".