21130223100 has 576 divisors, whose sum is σ = 77867016192. Its totient is φ = 4313088000.

The previous prime is 21130223099. The next prime is 21130223111. The reversal of 21130223100 is 132203112.

It is a super-2 number, since 2×21130223100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21130223100.

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 191 ways as a sum of consecutive naturals, for example, 67508544 + ... + 67508856.

It is an arithmetic number, because the mean of its divisors is an integer number (135185792).

Almost surely, 2^21130223100 is an apocalyptic number.

21130223100 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 21130223100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38933508096).

21130223100 is an abundant number, since it is smaller than the sum of its proper divisors (56736793092).

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

21130223100 is a wasteful number, since it uses less digits than its factorization.

21130223100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446 (or 439 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21130223100 its reverse (132203112), we get a palindrome (21262426212).

The spelling of 21130223100 in words is "twenty-one billion, one hundred thirty million, two hundred twenty-three thousand, one hundred".