20012111001 has 12 divisors (see below), whose sum is σ = 28938124800. Its totient is φ = 13326757080.

The previous prime is 20012110991. The next prime is 20012111023. The reversal of 20012111001 is 10011121002.

It is a happy number.

It is not a de Polignac number, because 20012111001 - 2²⁹ = 19475240089 is a prime.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20012111201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1212201 + ... + 1228598.

It is an arithmetic number, because the mean of its divisors is an integer number (2411510400).

Almost surely, 2^20012111001 is an apocalyptic number.

It is an amenable number.

20012111001 is a deficient number, since it is larger than the sum of its proper divisors (8926013799).

20012111001 is a wasteful number, since it uses less digits than its factorization.

20012111001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2441716 (or 2441713 counting only the distinct ones).

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

Adding to 20012111001 its reverse (10011121002), we get a palindrome (30023232003).

The spelling of 20012111001 in words is "twenty billion, twelve million, one hundred eleven thousand, one".