20001210120001 has 16 divisors (see below), whose sum is σ = 21974493637440. Its totient is φ = 18054118840320.

The previous prime is 20001210119999. The next prime is 20001210120077. The reversal of 20001210120001 is 10002101210002.

It is a cyclic number.

It is not a de Polignac number, because 20001210120001 - 2¹ = 20001210119999 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20001210120001.

It is not an unprimeable number, because it can be changed into a prime (20001210120301) 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, 7896556 + ... + 10117213.

It is an arithmetic number, because the mean of its divisors is an integer number (1373405852340).

Almost surely, 2^{20001210120001} is an apocalyptic number.

It is an amenable number.

20001210120001 is a deficient number, since it is larger than the sum of its proper divisors (1973283517439).

20001210120001 is a wasteful number, since it uses less digits than its factorization.

20001210120001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18014496.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20001210120001 its reverse (10002101210002), we get a palindrome (30003311330003).

The spelling of 20001210120001 in words is "twenty trillion, one billion, two hundred ten million, one hundred twenty thousand, one".