211264505 has 4 divisors (see below), whose sum is σ = 253517412. Its totient is φ = 169011600.

The previous prime is 211264447. The next prime is 211264523. The reversal of 211264505 is 505462112.

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 64176121 + 147088384 = 8011^2 + 12128^2 .

It is not a de Polignac number, because 211264505 - 2²⁴ = 194487289 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 21126446 + ... + 21126455.

It is an arithmetic number, because the mean of its divisors is an integer number (63379353).

Almost surely, 2^211264505 is an apocalyptic number.

It is an amenable number.

211264505 is a deficient number, since it is larger than the sum of its proper divisors (42252907).

211264505 is an equidigital number, since it uses as much as digits as its factorization.

211264505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42252906.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 211264505 is about 14534.9408323529. The cubic root of 211264505 is about 595.5828434206.

The spelling of 211264505 in words is "two hundred eleven million, two hundred sixty-four thousand, five hundred five".