21010210100 has 108 divisors (see below), whose sum is σ = 50381608704. Its totient is φ = 7599240000.

The previous prime is 21010210097. The next prime is 21010210141. The reversal of 21010210100 is 101201012.

It is a super-2 number, since 2×21010210100² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 2306555 + ... + 2315645.

Almost surely, 2^21010210100 is an apocalyptic number.

21010210100 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 21010210100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25190804352).

21010210100 is an abundant number, since it is smaller than the sum of its proper divisors (29371398604).

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

21010210100 is a wasteful number, since it uses less digits than its factorization.

21010210100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9318 (or 9300 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21010210100 its reverse (101201012), we get a palindrome (21111411112).

The spelling of 21010210100 in words is "twenty-one billion, ten million, two hundred ten thousand, one hundred".