20121002010091 has 4 divisors (see below), whose sum is σ = 20254253679184. Its totient is φ = 19987750341000.

The previous prime is 20121002010071. The next prime is 20121002010199. The reversal of 20121002010091 is 19001020012102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20121002010091 - 2⁵ = 20121002010059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20121002010001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66625834320 + ... + 66625834621.

It is an arithmetic number, because the mean of its divisors is an integer number (5063563419796).

Almost surely, 2^{20121002010091} is an apocalyptic number.

20121002010091 is a deficient number, since it is larger than the sum of its proper divisors (133251669093).

20121002010091 is a wasteful number, since it uses less digits than its factorization.

20121002010091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133251669092.

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

Adding to 20121002010091 its reverse (19001020012102), we get a palindrome (39122022022193).

The spelling of 20121002010091 in words is "twenty trillion, one hundred twenty-one billion, two million, ten thousand, ninety-one".