21001000100102 has 16 divisors (see below), whose sum is σ = 35859415191552. Its totient is φ = 9130869608520.

The previous prime is 21001000100081. The next prime is 21001000100107. The reversal of 21001000100102 is 20100100010012.

It is a self number, because there is not a number n which added to its sum of digits gives 21001000100102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001000100107) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 20751975878 + ... + 20751976889.

It is an arithmetic number, because the mean of its divisors is an integer number (2241213449472).

Almost surely, 2^{21001000100102} is an apocalyptic number.

21001000100102 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21001000100102 is a deficient number, since it is larger than the sum of its proper divisors (14858415091450).

21001000100102 is a wasteful number, since it uses less digits than its factorization.

21001000100102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41503952803.

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

Adding to 21001000100102 its reverse (20100100010012), we get a palindrome (41101100110114).

It can be divided in two parts, 2100100010010 and 2, that added together give a palindrome (2100100010012).

The spelling of 21001000100102 in words is "twenty-one trillion, one billion, one hundred thousand, one hundred two".