20001121012009 has 16 divisors (see below), whose sum is σ = 20551064480640. Its totient is φ = 19458390025600.

The previous prime is 20001121012007. The next prime is 20001121012027. The reversal of 20001121012009 is 90021012110002.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20001121012009 - 2¹ = 20001121012007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20001121012007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12050244 + ... + 13609210.

It is an arithmetic number, because the mean of its divisors is an integer number (1284441530040).

Almost surely, 2^{20001121012009} is an apocalyptic number.

It is an amenable number.

20001121012009 is a deficient number, since it is larger than the sum of its proper divisors (549943468631).

20001121012009 is a wasteful number, since it uses less digits than its factorization.

20001121012009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1561280.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 20001121012009 in words is "twenty trillion, one billion, one hundred twenty-one million, twelve thousand, nine".