215021197 has 2 divisors, whose sum is σ = 215021198. Its totient is φ = 215021196.

The previous prime is 215021189. The next prime is 215021201. The reversal of 215021197 is 791120512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 150283081 + 64738116 = 12259^2 + 8046^2 .

It is a cyclic number.

It is not a de Polignac number, because 215021197 - 2³ = 215021189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215021137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107510598 + 107510599.

It is an arithmetic number, because the mean of its divisors is an integer number (107510599).

Almost surely, 2^215021197 is an apocalyptic number.

It is an amenable number.

215021197 is a deficient number, since it is larger than the sum of its proper divisors (1).

215021197 is an equidigital number, since it uses as much as digits as its factorization.

215021197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 28.

The square root of 215021197 is about 14663.6010925011. The cubic root of 215021197 is about 599.0923285058.

The spelling of 215021197 in words is "two hundred fifteen million, twenty-one thousand, one hundred ninety-seven".