215195985 has 12 divisors (see below), whose sum is σ = 373006452. Its totient is φ = 114771168.

The previous prime is 215195947. The next prime is 215195987. The reversal of 215195985 is 589591512.

215195985 is a `hidden beast` number, since 2 + 1 + 51 + 9 + 598 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 39050001 + 176145984 = 6249^2 + 13272^2 .

It is not a de Polignac number, because 215195985 - 2⁷ = 215195857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 4782133 = 215195985 / (2 + 1 + 5 + 1 + 9 + 5 + 9 + 8 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 215195985.

It is not an unprimeable number, because it can be changed into a prime (215195987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2391022 + ... + 2391111.

It is an arithmetic number, because the mean of its divisors is an integer number (31083871).

Almost surely, 2^215195985 is an apocalyptic number.

It is an amenable number.

215195985 is a deficient number, since it is larger than the sum of its proper divisors (157810467).

215195985 is a wasteful number, since it uses less digits than its factorization.

215195985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4782144 (or 4782141 counting only the distinct ones).

The product of its digits is 162000, while the sum is 45.

The square root of 215195985 is about 14669.5598093467. The cubic root of 215195985 is about 599.2546160547.

The spelling of 215195985 in words is "two hundred fifteen million, one hundred ninety-five thousand, nine hundred eighty-five".