211404105691 has 2 divisors, whose sum is σ = 211404105692. Its totient is φ = 211404105690.

The previous prime is 211404105641. The next prime is 211404105707. The reversal of 211404105691 is 196501404112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211404105691 - 2²⁷ = 211269887963 is a prime.

It is a super-2 number, since 2×211404105691² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (211404105641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105702052845 + 105702052846.

It is an arithmetic number, because the mean of its divisors is an integer number (105702052846).

Almost surely, 2^211404105691 is an apocalyptic number.

211404105691 is a deficient number, since it is larger than the sum of its proper divisors (1).

211404105691 is an equidigital number, since it uses as much as digits as its factorization.

211404105691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 34.

The spelling of 211404105691 in words is "two hundred eleven billion, four hundred four million, one hundred five thousand, six hundred ninety-one".