21101100021002 has 16 divisors (see below), whose sum is σ = 34330914527112. Its totient is φ = 9687736020480.

The previous prime is 21101100020939. The next prime is 21101100021011. The reversal of 21101100021002 is 20012000110112.

It can be written as a sum of positive squares in 4 ways, for example, as 20666015988121 + 435084032881 = 4545989^2 + 659609^2 .

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, 7568542373 + ... + 7568545160.

Almost surely, 2^{21101100021002} is an apocalyptic number.

21101100021002 is a deficient number, since it is larger than the sum of its proper divisors (13229814506110).

21101100021002 is a wasteful number, since it uses less digits than its factorization.

21101100021002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15137087593.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21101100021002 its reverse (20012000110112), we get a palindrome (41113100131114).

The spelling of 21101100021002 in words is "twenty-one trillion, one hundred one billion, one hundred million, twenty-one thousand, two".