215403197 has 2 divisors, whose sum is σ = 215403198. Its totient is φ = 215403196.

The previous prime is 215403187. The next prime is 215403203. The reversal of 215403197 is 791304512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116877721 + 98525476 = 10811^2 + 9926^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215403197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215403127) 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, 107701598 + 107701599.

It is an arithmetic number, because the mean of its divisors is an integer number (107701599).

Almost surely, 2^215403197 is an apocalyptic number.

It is an amenable number.

215403197 is a deficient number, since it is larger than the sum of its proper divisors (1).

215403197 is an equidigital number, since it uses as much as digits as its factorization.

215403197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 215403197 is about 14676.6207622872. The cubic root of 215403197 is about 599.4468949109.

The spelling of 215403197 in words is "two hundred fifteen million, four hundred three thousand, one hundred ninety-seven".