215301997 has 2 divisors, whose sum is σ = 215301998. Its totient is φ = 215301996.

The previous prime is 215301979. The next prime is 215302051. The reversal of 215301997 is 799103512.

Together with previous prime (215301979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 165019716 + 50282281 = 12846^2 + 7091^2 .

It is a cyclic number.

It is not a de Polignac number, because 215301997 - 2¹¹ = 215299949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215301197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107650998 + 107650999.

It is an arithmetic number, because the mean of its divisors is an integer number (107650999).

Almost surely, 2^215301997 is an apocalyptic number.

It is an amenable number.

215301997 is a deficient number, since it is larger than the sum of its proper divisors (1).

215301997 is an equidigital number, since it uses as much as digits as its factorization.

215301997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17010, while the sum is 37.

The square root of 215301997 is about 14673.1726971368. The cubic root of 215301997 is about 599.3530035026.

The spelling of 215301997 in words is "two hundred fifteen million, three hundred one thousand, nine hundred ninety-seven".