2001201101172 has 144 divisors (see below), whose sum is σ = 6229392798720. Its totient is φ = 527498210304.

The previous prime is 2001201101171. The next prime is 2001201101173. The reversal of 2001201101172 is 2711011021002.

It is an interprime number because it is at equal distance from previous prime (2001201101171) and next prime (2001201101173).

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 (2001201101171) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5804604 + ... + 6139692.

Almost surely, 2^{2001201101172} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2001201101172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3114696399360).

2001201101172 is an abundant number, since it is smaller than the sum of its proper divisors (4228191697548).

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

2001201101172 is a wasteful number, since it uses less digits than its factorization.

2001201101172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336942 (or 336937 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 18.

Adding to 2001201101172 its reverse (2711011021002), we get a palindrome (4712212122174).

The spelling of 2001201101172 in words is "two trillion, one billion, two hundred one million, one hundred one thousand, one hundred seventy-two".