21010010100 has 72 divisors (see below), whose sum is σ = 63431981760. Its totient is φ = 5359073280.

The previous prime is 21010010093. The next prime is 21010010113. The reversal of 21010010100 is 101001012.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1515565 + ... + 1529364.

Almost surely, 2^21010010100 is an apocalyptic number.

21010010100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010010100 is an abundant number, since it is smaller than the sum of its proper divisors (42421971660).

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

21010010100 is a wasteful number, since it uses less digits than its factorization.

21010010100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3044969 (or 3044962 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 6.

Adding to 21010010100 its reverse (101001012), we get a palindrome (21111011112).

The spelling of 21010010100 in words is "twenty-one billion, ten million, ten thousand, one hundred".