211774969906261 has 2 divisors, whose sum is σ = 211774969906262. Its totient is φ = 211774969906260.

The previous prime is 211774969906117. The next prime is 211774969906271. The reversal of 211774969906261 is 162609969477112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153830812151025 + 57944157755236 = 12402855^2 + 7612106^2 .

It is a cyclic number.

It is not a de Polignac number, because 211774969906261 - 2¹³ = 211774969898069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211774969906271) 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, 105887484953130 + 105887484953131.

It is an arithmetic number, because the mean of its divisors is an integer number (105887484953131).

Almost surely, 2^{211774969906261} is an apocalyptic number.

It is an amenable number.

211774969906261 is a deficient number, since it is larger than the sum of its proper divisors (1).

211774969906261 is an equidigital number, since it uses as much as digits as its factorization.

211774969906261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 123451776, while the sum is 70.

The spelling of 211774969906261 in words is "two hundred eleven trillion, seven hundred seventy-four billion, nine hundred sixty-nine million, nine hundred six thousand, two hundred sixty-one".