215605213 has 2 divisors, whose sum is σ = 215605214. Its totient is φ = 215605212.

The previous prime is 215605211. The next prime is 215605223. The reversal of 215605213 is 312506512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 192737689 + 22867524 = 13883^2 + 4782^2 .

It is a cyclic number.

It is not a de Polignac number, because 215605213 - 2¹ = 215605211 is a prime.

Together with 215605211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215605211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107802606 + 107802607.

It is an arithmetic number, because the mean of its divisors is an integer number (107802607).

Almost surely, 2^215605213 is an apocalyptic number.

It is an amenable number.

215605213 is a deficient number, since it is larger than the sum of its proper divisors (1).

215605213 is an equidigital number, since it uses as much as digits as its factorization.

215605213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 215605213 is about 14683.5013876119. The cubic root of 215605213 is about 599.6342335516.

The spelling of 215605213 in words is "two hundred fifteen million, six hundred five thousand, two hundred thirteen".