211426340465 has 4 divisors (see below), whose sum is σ = 253711608564. Its totient is φ = 169141072368.

The previous prime is 211426340453. The next prime is 211426340491. The reversal of 211426340465 is 564043624112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 42360637489 + 169065702976 = 205817^2 + 411176^2 .

It is a cyclic number.

It is not a de Polignac number, because 211426340465 - 2²⁸ = 211157905009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21142634042 + ... + 21142634051.

It is an arithmetic number, because the mean of its divisors is an integer number (63427902141).

Almost surely, 2^211426340465 is an apocalyptic number.

It is an amenable number.

211426340465 is a deficient number, since it is larger than the sum of its proper divisors (42285268099).

211426340465 is an equidigital number, since it uses as much as digits as its factorization.

211426340465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42285268098.

The product of its (nonzero) digits is 138240, while the sum is 38.

Adding to 211426340465 its reverse (564043624112), we get a palindrome (775469964577).

The spelling of 211426340465 in words is "two hundred eleven billion, four hundred twenty-six million, three hundred forty thousand, four hundred sixty-five".