212247605 has 4 divisors (see below), whose sum is σ = 254697132. Its totient is φ = 169798080.

The previous prime is 212247599. The next prime is 212247617. The reversal of 212247605 is 506742212.

It is a happy number.

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 98227921 + 114019684 = 9911^2 + 10678^2 .

It is not a de Polignac number, because 212247605 - 2²⁰ = 211199029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 21224756 + ... + 21224765.

It is an arithmetic number, because the mean of its divisors is an integer number (63674283).

Almost surely, 2^212247605 is an apocalyptic number.

It is an amenable number.

212247605 is a deficient number, since it is larger than the sum of its proper divisors (42449527).

212247605 is an equidigital number, since it uses as much as digits as its factorization.

212247605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42449526.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 212247605 is about 14568.7200879144. The cubic root of 212247605 is about 596.5052441756.

Adding to 212247605 its reverse (506742212), we get a palindrome (718989817).

The spelling of 212247605 in words is "two hundred twelve million, two hundred forty-seven thousand, six hundred five".