2001012312221 has 16 divisors (see below), whose sum is σ = 2191615144320. Its totient is φ = 1815653724480.

The previous prime is 2001012312203. The next prime is 2001012312263. The reversal of 2001012312221 is 1222132101002.

It is a cyclic number.

It is not a de Polignac number, because 2001012312221 - 2⁶ = 2001012312157 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2001012312221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001012312121) 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, 11798936 + ... + 11967326.

It is an arithmetic number, because the mean of its divisors is an integer number (136975946520).

Almost surely, 2^{2001012312221} is an apocalyptic number.

It is an amenable number.

2001012312221 is a deficient number, since it is larger than the sum of its proper divisors (190602832099).

2001012312221 is a wasteful number, since it uses less digits than its factorization.

2001012312221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183956.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 2001012312221 its reverse (1222132101002), we get a palindrome (3223144413223).

The spelling of 2001012312221 in words is "two trillion, one billion, twelve million, three hundred twelve thousand, two hundred twenty-one".