21000012100206 has 16 divisors (see below), whose sum is σ = 42688549188048. Its totient is φ = 6885249868800.

The previous prime is 21000012100181. The next prime is 21000012100213. The reversal of 21000012100206 is 60200121000012.

It is a congruent number.

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, 28688540755 + ... + 28688541486.

It is an arithmetic number, because the mean of its divisors is an integer number (2668034324253).

Almost surely, 2^{21000012100206} is an apocalyptic number.

21000012100206 is an abundant number, since it is smaller than the sum of its proper divisors (21688537087842).

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

21000012100206 is a wasteful number, since it uses less digits than its factorization.

21000012100206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57377082307.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21000012100206 its reverse (60200121000012), we get a palindrome (81200133100218).

The spelling of 21000012100206 in words is "twenty-one trillion, twelve million, one hundred thousand, two hundred six".