2001012100221 has 16 divisors (see below), whose sum is σ = 2761919012160. Its totient is φ = 1287120038400.

The previous prime is 2001012100201. The next prime is 2001012100229. The reversal of 2001012100221 is 1220012101002.

It is not a de Polignac number, because 2001012100221 - 2¹⁹ = 2001011575933 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2001012100197 and 2001012100206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001012100229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7799380 + ... + 8051853.

It is an arithmetic number, because the mean of its divisors is an integer number (172619938260).

Almost surely, 2^{2001012100221} is an apocalyptic number.

It is an amenable number.

2001012100221 is a deficient number, since it is larger than the sum of its proper divisors (760906911939).

2001012100221 is a wasteful number, since it uses less digits than its factorization.

2001012100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15852716.

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

Adding to 2001012100221 its reverse (1220012101002), we get a palindrome (3221024201223).

The spelling of 2001012100221 in words is "two trillion, one billion, twelve million, one hundred thousand, two hundred twenty-one".