211664423 has 16 divisors (see below), whose sum is σ = 224280576. Its totient is φ = 199362240.

The previous prime is 211664413. The next prime is 211664441. The reversal of 211664423 is 324466112.

It is a cyclic number.

It is not a de Polignac number, because 211664423 - 2¹⁰ = 211663399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211664413) 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 in 15 ways as a sum of consecutive naturals, for example, 680438 + ... + 680748.

It is an arithmetic number, because the mean of its divisors is an integer number (14017536).

Almost surely, 2^211664423 is an apocalyptic number.

211664423 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

211664423 is a deficient number, since it is larger than the sum of its proper divisors (12616153).

211664423 is a wasteful number, since it uses less digits than its factorization.

211664423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694.

The product of its digits is 6912, while the sum is 29.

The square root of 211664423 is about 14548.6914531857. The cubic root of 211664423 is about 595.9584139490.

The spelling of 211664423 in words is "two hundred eleven million, six hundred sixty-four thousand, four hundred twenty-three".