211540423 has 2 divisors, whose sum is σ = 211540424. Its totient is φ = 211540422.

The previous prime is 211540411. The next prime is 211540447. The reversal of 211540423 is 324045112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211540423 is a prime.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 211540394 and 211540403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211540493) 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 as a sum of consecutive naturals, namely, 105770211 + 105770212.

It is an arithmetic number, because the mean of its divisors is an integer number (105770212).

Almost surely, 2^211540423 is an apocalyptic number.

211540423 is a deficient number, since it is larger than the sum of its proper divisors (1).

211540423 is an equidigital number, since it uses as much as digits as its factorization.

211540423 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 211540423 is about 14544.4292772181. The cubic root of 211540423 is about 595.8420138509.

Adding to 211540423 its reverse (324045112), we get a palindrome (535585535).

The spelling of 211540423 in words is "two hundred eleven million, five hundred forty thousand, four hundred twenty-three".