215711213 has 4 divisors (see below), whose sum is σ = 216144000. Its totient is φ = 215278428.

The previous prime is 215711203. The next prime is 215711239. The reversal of 215711213 is 312117512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 215711213 - 2¹² = 215707117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215711203) 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, 215645 + ... + 216642.

It is an arithmetic number, because the mean of its divisors is an integer number (54036000).

Almost surely, 2^215711213 is an apocalyptic number.

It is an amenable number.

215711213 is a deficient number, since it is larger than the sum of its proper divisors (432787).

215711213 is an equidigital number, since it uses as much as digits as its factorization.

215711213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432786.

The product of its digits is 420, while the sum is 23.

The square root of 215711213 is about 14687.1104373869. The cubic root of 215711213 is about 599.7324853739.

Adding to 215711213 its reverse (312117512), we get a palindrome (527828725).

The spelling of 215711213 in words is "two hundred fifteen million, seven hundred eleven thousand, two hundred thirteen".