212215345 has 4 divisors (see below), whose sum is σ = 254658420. Its totient is φ = 169772272.

The previous prime is 212215343. The next prime is 212215361. The reversal of 212215345 is 543512212.

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 148279329 + 63936016 = 12177^2 + 7996^2 .

It is a cyclic number.

It is not a de Polignac number, because 212215345 - 2¹ = 212215343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (212215343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21221530 + ... + 21221539.

It is an arithmetic number, because the mean of its divisors is an integer number (63664605).

Almost surely, 2^212215345 is an apocalyptic number.

It is an amenable number.

212215345 is a deficient number, since it is larger than the sum of its proper divisors (42443075).

212215345 is an equidigital number, since it uses as much as digits as its factorization.

212215345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42443074.

The product of its digits is 2400, while the sum is 25.

The square root of 212215345 is about 14567.6128792606. The cubic root of 212215345 is about 596.4750212446.

Adding to 212215345 its reverse (543512212), we get a palindrome (755727557).

The spelling of 212215345 in words is "two hundred twelve million, two hundred fifteen thousand, three hundred forty-five".