21001200012102 has 24 divisors (see below), whose sum is σ = 42726371339736. Its totient is φ = 6881749149664.

The previous prime is 21001200012049. The next prime is 21001200012119. The reversal of 21001200012102 is 20121000210012.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 502736943 + ... + 502778714.

It is an arithmetic number, because the mean of its divisors is an integer number (1780265472489).

Almost surely, 2^{21001200012102} is an apocalyptic number.

21001200012102 is an abundant number, since it is smaller than the sum of its proper divisors (21725171327634).

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

21001200012102 is a wasteful number, since it uses less digits than its factorization.

21001200012102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005515780 (or 1005515721 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21001200012102 its reverse (20121000210012), we get a palindrome (41122200222114).

The spelling of 21001200012102 in words is "twenty-one trillion, one billion, two hundred million, twelve thousand, one hundred two".