215530247 has 2 divisors, whose sum is σ = 215530248. Its totient is φ = 215530246.

The previous prime is 215530213. The next prime is 215530261. The reversal of 215530247 is 742035512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 215530247 - 2¹² = 215526151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215533247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107765123 + 107765124.

It is an arithmetic number, because the mean of its divisors is an integer number (107765124).

Almost surely, 2^215530247 is an apocalyptic number.

215530247 is a deficient number, since it is larger than the sum of its proper divisors (1).

215530247 is an equidigital number, since it uses as much as digits as its factorization.

215530247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8400, while the sum is 29.

The square root of 215530247 is about 14680.9484366644. The cubic root of 215530247 is about 599.5647278251.

Adding to 215530247 its reverse (742035512), we get a palindrome (957565759).

The spelling of 215530247 in words is "two hundred fifteen million, five hundred thirty thousand, two hundred forty-seven".