20211312091 has 2 divisors, whose sum is σ = 20211312092. Its totient is φ = 20211312090.

The previous prime is 20211312067. The next prime is 20211312127. The reversal of 20211312091 is 19021311202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20211312091 - 2¹⁵ = 20211279323 is a prime.

It is not a weakly prime, because it can be changed into another prime (20211312391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105656045 + 10105656046.

It is an arithmetic number, because the mean of its divisors is an integer number (10105656046).

Almost surely, 2^20211312091 is an apocalyptic number.

20211312091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211312091 is an equidigital number, since it uses as much as digits as its factorization.

20211312091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

Adding to 20211312091 its reverse (19021311202), we get a palindrome (39232623293).

The spelling of 20211312091 in words is "twenty billion, two hundred eleven million, three hundred twelve thousand, ninety-one".