21100100212 has 24 divisors (see below), whose sum is σ = 37004574600. Its totient is φ = 10527390720.

The previous prime is 21100100179. The next prime is 21100100221. The reversal of 21100100212 is 21200100112.

It can be written as a sum of positive squares in 4 ways, for example, as 3864611556 + 17235488656 = 62166^2 + 131284^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5209164 + ... + 5213212.

It is an arithmetic number, because the mean of its divisors is an integer number (1541857275).

Almost surely, 2^21100100212 is an apocalyptic number.

It is an amenable number.

21100100212 is a deficient number, since it is larger than the sum of its proper divisors (15904474388).

21100100212 is a wasteful number, since it uses less digits than its factorization.

21100100212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6531 (or 6529 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21100100212 its reverse (21200100112), we get a palindrome (42300200324).

The spelling of 21100100212 in words is "twenty-one billion, one hundred million, one hundred thousand, two hundred twelve".