21000012100207 has 16 divisors (see below), whose sum is σ = 25198161730560. Its totient is φ = 17119927506528.

The previous prime is 21000012100181. The next prime is 21000012100213. The reversal of 21000012100207 is 70200121000012.

It is not a de Polignac number, because 21000012100207 - 2¹⁹ = 21000011575919 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000012100247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 771988903 + ... + 772016104.

It is an arithmetic number, because the mean of its divisors is an integer number (1574885108160).

Almost surely, 2^{21000012100207} is an apocalyptic number.

21000012100207 is a deficient number, since it is larger than the sum of its proper divisors (4198149630353).

21000012100207 is a wasteful number, since it uses less digits than its factorization.

21000012100207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1544005110.

The product of its (nonzero) digits is 56, while the sum is 16.

Adding to 21000012100207 its reverse (70200121000012), we get a palindrome (91200133100219).

The spelling of 21000012100207 in words is "twenty-one trillion, twelve million, one hundred thousand, two hundred seven".