2001100101001 has 4 divisors (see below), whose sum is σ = 2011257969732. Its totient is φ = 1990942232272.

The previous prime is 2001100100983. The next prime is 2001100101061. The reversal of 2001100101001 is 1001010011002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1222074975625 + 779025125376 = 1105475^2 + 882624^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001100101001 - 2¹³ = 2001100092809 is a prime.

It is a super-2 number, since 2×2001100101001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2001100101061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5078934070 + ... + 5078934463.

It is an arithmetic number, because the mean of its divisors is an integer number (502814492433).

Almost surely, 2^{2001100101001} is an apocalyptic number.

It is an amenable number.

2001100101001 is a deficient number, since it is larger than the sum of its proper divisors (10157868731).

2001100101001 is a wasteful number, since it uses less digits than its factorization.

2001100101001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10157868730.

The product of its (nonzero) digits is 2, while the sum is 7.

Adding to 2001100101001 its reverse (1001010011002), we get a palindrome (3002110112003).

The spelling of 2001100101001 in words is "two trillion, one billion, one hundred million, one hundred one thousand, one".