21100113210 has 128 divisors (see below), whose sum is σ = 60075074304. Its totient is φ = 4684124160.

The previous prime is 21100113163. The next prime is 21100113211. The reversal of 21100113210 is 1231100112.

It is not an unprimeable number, because it can be changed into a prime (21100113211) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 156744 + ... + 258396.

It is an arithmetic number, because the mean of its divisors is an integer number (469336518).

Almost surely, 2^21100113210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100113210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30037537152).

21100113210 is an abundant number, since it is smaller than the sum of its proper divisors (38974961094).

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

21100113210 is a wasteful number, since it uses less digits than its factorization.

21100113210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101728.

The product of its (nonzero) digits is 12, while the sum is 12.

Adding to 21100113210 its reverse (1231100112), we get a palindrome (22331213322).

The spelling of 21100113210 in words is "twenty-one billion, one hundred million, one hundred thirteen thousand, two hundred ten".