20012121222091 has 2 divisors, whose sum is σ = 20012121222092. Its totient is φ = 20012121222090.

The previous prime is 20012121222061. The next prime is 20012121222131. The reversal of 20012121222091 is 19022212121002.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20012121222091 - 2⁵ = 20012121222059 is a prime.

It is not a weakly prime, because it can be changed into another prime (20012121222061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006060611045 + 10006060611046.

It is an arithmetic number, because the mean of its divisors is an integer number (10006060611046).

Almost surely, 2^{20012121222091} is an apocalyptic number.

20012121222091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012121222091 is an equidigital number, since it uses as much as digits as its factorization.

20012121222091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 25.

Adding to 20012121222091 its reverse (19022212121002), we get a palindrome (39034333343093).

The spelling of 20012121222091 in words is "twenty trillion, twelve billion, one hundred twenty-one million, two hundred twenty-two thousand, ninety-one".