215142247 has 2 divisors, whose sum is σ = 215142248. Its totient is φ = 215142246.

The previous prime is 215142241. The next prime is 215142251. The reversal of 215142247 is 742241512.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215142247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215142241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107571123 + 107571124.

It is an arithmetic number, because the mean of its divisors is an integer number (107571124).

Almost surely, 2^215142247 is an apocalyptic number.

215142247 is a deficient number, since it is larger than the sum of its proper divisors (1).

215142247 is an equidigital number, since it uses as much as digits as its factorization.

215142247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4480, while the sum is 28.

The square root of 215142247 is about 14667.7280790176. The cubic root of 215142247 is about 599.2047306360.

Adding to 215142247 its reverse (742241512), we get a palindrome (957383759).

The spelling of 215142247 in words is "two hundred fifteen million, one hundred forty-two thousand, two hundred forty-seven".