20111001002001 has 96 divisors (see below), whose sum is σ = 37770410845440. Its totient is φ = 10349268134400.

The previous prime is 20111001001943. The next prime is 20111001002033. The reversal of 20111001002001 is 10020010011102.

It is a happy number.

It is not a de Polignac number, because 20111001002001 - 2⁷ = 20111001001873 is a prime.

It is a super-2 number, since 2×20111001002001² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (20111001001001) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6368830 + ... + 8987991.

It is an arithmetic number, because the mean of its divisors is an integer number (393441779640).

Almost surely, 2^{20111001002001} is an apocalyptic number.

20111001002001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20111001002001 is a deficient number, since it is larger than the sum of its proper divisors (17659409843439).

20111001002001 is a wasteful number, since it uses less digits than its factorization.

20111001002001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15356904 (or 15356885 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20111001002001 its reverse (10020010011102), we get a palindrome (30131011013103).

The spelling of 20111001002001 in words is "twenty trillion, one hundred eleven billion, one million, two thousand, one".