21442312100 has 72 divisors (see below), whose sum is σ = 50887430496. Its totient is φ = 7777600000.

The previous prime is 21442312091. The next prime is 21442312147. The reversal of 21442312100 is 121324412.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 416795 + ... + 465405.

It is an arithmetic number, because the mean of its divisors is an integer number (706769868).

Almost surely, 2^21442312100 is an apocalyptic number.

21442312100 is a gapful number since it is divisible by the number (20) 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 21442312100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25443715248).

21442312100 is an abundant number, since it is smaller than the sum of its proper divisors (29445118396).

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

21442312100 is a wasteful number, since it uses less digits than its factorization.

21442312100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49037 (or 49030 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21442312100 its reverse (121324412), we get a palindrome (21563636512).

The spelling of 21442312100 in words is "twenty-one billion, four hundred forty-two million, three hundred twelve thousand, one hundred".