2001021121212 has 24 divisors (see below), whose sum is σ = 4693241253456. Its totient is φ = 663551044608.

The previous prime is 2001021121207. The next prime is 2001021121213. The reversal of 2001021121212 is 2121211201002.

It is a junction number, because it is equal to n+sod(n) for n = 2001021121191 and 2001021121200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001021121213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 431997063 + ... + 432001694.

It is an arithmetic number, because the mean of its divisors is an integer number (195551718894).

Almost surely, 2^{2001021121212} is an apocalyptic number.

It is an amenable number.

2001021121212 is an abundant number, since it is smaller than the sum of its proper divisors (2692220132244).

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

2001021121212 is a wasteful number, since it uses less digits than its factorization.

2001021121212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 863998957 (or 863998955 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 2001021121212 its reverse (2121211201002), we get a palindrome (4122232322214).

The spelling of 2001021121212 in words is "two trillion, one billion, twenty-one million, one hundred twenty-one thousand, two hundred twelve".