211530755 has 4 divisors (see below), whose sum is σ = 253836912. Its totient is φ = 169224600.

The previous prime is 211530749. The next prime is 211530757. The reversal of 211530755 is 557035112.

It is a happy number.

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

It is not a de Polignac number, because 211530755 - 2²⁰ = 210482179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211530757) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21153071 + ... + 21153080.

It is an arithmetic number, because the mean of its divisors is an integer number (63459228).

Almost surely, 2^211530755 is an apocalyptic number.

211530755 is a deficient number, since it is larger than the sum of its proper divisors (42306157).

211530755 is an equidigital number, since it uses as much as digits as its factorization.

211530755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42306156.

The product of its (nonzero) digits is 5250, while the sum is 29.

The square root of 211530755 is about 14544.0969124934. The cubic root of 211530755 is about 595.8329364867.

Adding to 211530755 its reverse (557035112), we get a palindrome (768565867).

The spelling of 211530755 in words is "two hundred eleven million, five hundred thirty thousand, seven hundred fifty-five".