21101223132 has 288 divisors, whose sum is σ = 62275239936. Its totient is φ = 5961859200.

The previous prime is 21101223131. The next prime is 21101223193. The reversal of 21101223132 is 23132210112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101223131) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 77864157 + ... + 77864427.

It is an arithmetic number, because the mean of its divisors is an integer number (216233472).

Almost surely, 2^21101223132 is an apocalyptic number.

21101223132 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21101223132, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31137619968).

21101223132 is an abundant number, since it is smaller than the sum of its proper divisors (41174016804).

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

21101223132 is a wasteful number, since it uses less digits than its factorization.

21101223132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501 (or 496 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21101223132 its reverse (23132210112), we get a palindrome (44233433244).

The spelling of 21101223132 in words is "twenty-one billion, one hundred one million, two hundred twenty-three thousand, one hundred thirty-two".