20211010212091 has 2 divisors, whose sum is σ = 20211010212092. Its totient is φ = 20211010212090.

The previous prime is 20211010212007. The next prime is 20211010212109. The reversal of 20211010212091 is 19021201011202.

Together with next prime (20211010212109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20211010212091 is a prime.

It is not a weakly prime, because it can be changed into another prime (20211010242091) 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 as a sum of consecutive naturals, namely, 10105505106045 + 10105505106046.

It is an arithmetic number, because the mean of its divisors is an integer number (10105505106046).

Almost surely, 2^{20211010212091} is an apocalyptic number.

20211010212091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211010212091 is an equidigital number, since it uses as much as digits as its factorization.

20211010212091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

Adding to 20211010212091 its reverse (19021201011202), we get a palindrome (39232211223293).

The spelling of 20211010212091 in words is "twenty trillion, two hundred eleven billion, ten million, two hundred twelve thousand, ninety-one".