21001100102 has 48 divisors (see below), whose sum is σ = 34379089920. Its totient is φ = 9594631440.

The previous prime is 21001100053. The next prime is 21001100117. The reversal of 21001100102 is 20100110012.

It is a self number, because there is not a number n which added to its sum of digits gives 21001100102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13401323 + ... + 13402889.

It is an arithmetic number, because the mean of its divisors is an integer number (716231040).

Almost surely, 2^21001100102 is an apocalyptic number.

21001100102 is a deficient number, since it is larger than the sum of its proper divisors (13377989818).

21001100102 is a wasteful number, since it uses less digits than its factorization.

21001100102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2017 (or 1986 counting only the distinct ones).

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

Adding to 21001100102 its reverse (20100110012), we get a palindrome (41101210114).

It can be divided in two parts, 2100110010 and 2, that added together give a palindrome (2100110012).

The spelling of 21001100102 in words is "twenty-one billion, one million, one hundred thousand, one hundred two".