2001221120142 has 80 divisors (see below), whose sum is σ = 4510102647600. Its totient is φ = 663233235840.

The previous prime is 2001221120141. The next prime is 2001221120153. The reversal of 2001221120142 is 2410211221002.

2001221120142 is a `hidden beast` number, since 200 + 1 + 221 + 1 + 201 + 42 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001221120141) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 21350034 + ... + 21443562.

It is an arithmetic number, because the mean of its divisors is an integer number (56376283095).

Almost surely, 2^{2001221120142} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2001221120142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2255051323800).

2001221120142 is an abundant number, since it is smaller than the sum of its proper divisors (2508881527458).

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

2001221120142 is a wasteful number, since it uses less digits than its factorization.

2001221120142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94303 (or 94294 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 2001221120142 its reverse (2410211221002), we get a palindrome (4411432341144).

The spelling of 2001221120142 in words is "two trillion, one billion, two hundred twenty-one million, one hundred twenty thousand, one hundred forty-two".