20111000001001 has 24 divisors (see below), whose sum is σ = 25257461276040. Its totient is φ = 15871919196672.

The previous prime is 20111000000957. The next prime is 20111000001013. The reversal of 20111000001001 is 10010000011102.

It can be written as a sum of positive squares in 4 ways, for example, as 134131737600 + 19976868263401 = 366240^2 + 4469549^2 .

It is not a de Polignac number, because 20111000001001 - 2⁷ = 20111000000873 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (7).

It is not an unprimeable number, because it can be changed into a prime (20111000001091) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 39509616 + ... + 40015393.

It is an arithmetic number, because the mean of its divisors is an integer number (1052394219835).

Almost surely, 2^{20111000001001} is an apocalyptic number.

It is an amenable number.

20111000001001 is a deficient number, since it is larger than the sum of its proper divisors (5146461275039).

20111000001001 is a wasteful number, since it uses less digits than its factorization.

20111000001001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79525433 (or 79525426 counting only the distinct ones).

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

Adding to 20111000001001 its reverse (10010000011102), we get a palindrome (30121000012103).

The spelling of 20111000001001 in words is "twenty trillion, one hundred eleven billion, one thousand, one".